Stuff

TODO.org

@@ -14,9 +14,6 @@
 :PROPERTIES:
 :CREATED:  [2022-05-16 Mon 22:12]
 :END:
-:LOGBOOK:
-CLOCK: [2022-06-01 Wed 16:47]
-:END:
 
 #+begin_src reason
   [@bs.module "react"]
@@ -30,6 +27,19 @@ CLOCK: [2022-06-01 Wed 16:47]
 - [[https://blog.bitsrc.io/build-our-own-react-redux-using-usereducer-and-usecontext-hooks-a5574b526475][Build Your Own React-Redux Using useReducer and useContext Hooks | by Chidume Nnamdi | Bits and Pieces]]
 
 ** TODO Headline content parser
+:LOGBOOK:
+CLOCK: [2022-08-09 Tue 17:51]--[2022-08-09 Tue 19:51] =>  2:00
+:END:
+
+So I've had some heavy misconceptions while working on the content,
+I would preparse all content tokens, just to work over them, but that doesn't make sense.
+Now w
+
+Currently I have a big problem that newline is not pure and interferes with the other function builders
+
+[[file:src/org/org_block_heading.nim::let contentEndParser = choice(@\[][This]] doesnt work because newline is "impure"
+
+Gonna convert everything to funcs.....
 ** TODO Store the line numbers :PARSER:
 ** TODO Tag parser :PARSER:
 ** TODO Creating hot reload :DEV_ENVIRONMENT:

docs/spec.org

@@ -1,5 +1,14 @@
 #+TITLE: Spec
 
+- dsfsd
+  1. 23231o
+
+     #+begin_src
+
+     #+end_src
+
+          - sdfsdfsdf
+  - sdfsdfsdf
 
 * Specs
 

src/org/org_block_heading.nim

@@ -33,11 +33,14 @@ let parseTodoKeyword = todoKeywords.createTodoKeywordParser()
 let parseDoneKeyword = doneKeywords.createTodoKeywordParser()
 
 let parseContentText = @[
-  anyUntil(choice(@[endOfStream, str("\n*")])),
+  anyUntil(choice(@[endOfStream, str("\n")])),
 ]
 
 let parseHeadlineNewline = @[
-  ignore(newline)
+  choice(@[
+    ch(NewLines),
+    endOfStream,
+  ])
 ]
 
 let parseHeadingText = @[
@@ -91,9 +94,9 @@ proc tryBuildHeading(builder: OrgBuilderResult): OrgBuilderResult =
 
       (parseHeadingText, buildHeadlineContent, false),
 
-      (parseContentText, buildHeadlineChildren, true),
+      # (parseContentText, buildHeadlineChildren, true),
 
-      (parseHeadlineNewline, buildHeadlineNewline, true),
+      (parseHeadlineNewline, buildHeadlineNewline, false),
     ]
   )
 
@@ -102,7 +105,8 @@ let headingParser = choice(@[
   endOfStream,
 ])
 
-let newlineParser: seq[Parser -> ParserResult] = @[newline + newline]
+
+let contentEndParser = newline
 
 let buildNewline = func(tokens: seq[ParserToken], org: OrgBlock): OrgBlock {.closure.} =
   OrgBlock(
@@ -111,44 +115,63 @@ let buildNewline = func(tokens: seq[ParserToken], org: OrgBlock): OrgBlock {.clo
 
 proc concatOrgBlock(xs: seq[OrgBlock], ys: seq[OrgBlock]): seq[OrgBlock] = xs & ys
 
+let parseBlockText = @[
+  anyUntil(choice(@[endOfStream, str("\n")])),
+]
+
 let contentParsersSeq: seq[tuple[
   parsers: seq[Parser -> ParserResult],
   tokenFoldFn: (seq[ParserToken], OrgBlock) -> OrgBlock,
   ignoreEmpty: bool,
   # concatFn: (seq[OrgBlock], seq[OrgBlock]) -> seq[OrgBlock],
 ]] = @[
-  (newlineParser, buildNewline, false),
+  (parseBlockText, buildNewline, true),
-  # (newlineParser, buildNewline, false),
+  (contentEndParser, buildNewline, true),
 ]
 
 proc parseHeadlineChildren(builder: OrgBuilder): OrgBuilderResult =
   var headingBlock = builder.tree[0]
 
-  var builderAcc: OrgBuilderResult = OrgBuilderResult.ok(builder)
+  # echo "Builder " & $builder
 
+  # var builderAcc: OrgBuilderResult = OrgBuilderResult.ok(builder)
+  var builderAcc: OrgBuilderResult = OrgBuilderResult.ok(OrgBuilder(
+    (
+      parser: builder.parser,
+      tree: @[],
+  )
+  ))
+
+  echo "builderAcc before parse content ", builderAcc
+  # echo builderAcc.tryParser(headingParser)
   while builderAcc.isOk() and builderAcc.tryParser(headingParser).isErr():
     builderAcc = builderAcc
       .applyParsersSeqToSeq(
         contentParsersSeq
       )
+    echo "builderAcc after parse in while loop ", builderAcc
+    # echo builderAcc
 
-  builderAcc
 
-  # let content = builderAcc.fold(
+  let content = builderAcc.fold(
-  #   (_err) => "",
+    (err) => 0, # newSeq[OrgBlock](),
-  #   (builder: OrgBuilder) => builder.tree,
+    (builder: OrgBuilder) => len builder.tree,
-  # )
+  )
+
+  # echo "builderAcc" & $builderAcc
+  echo "content" & $content
+
   # headingBlock.content = content
 
-  # let res = builderAcc.fold(
+  let res = builderAcc.fold(
-  #   (_err) => OrgBuilderResult.err((builder, "Could not parse content")),
+    (err) => OrgBuilderResult.err((builder, "Could not parse content")),
-  #   (builder: OrgBuilder) => OrgBuilderResult.ok((
+    (builder: OrgBuilder) => OrgBuilderResult.ok((
-  #       parser: builder.parser.emptyTokens(),
+        parser: builder.parser.emptyTokens(),
-  #       tree: @[headingBlock],
+        tree: @[headingBlock],
-  #   ))
+    ))
-  # )
+  )
 
-  # res
+  res
 
 proc makeOrg*(x: string): OrgBuilderResult =
   var acc = initOrgBuilder(x)
@@ -181,14 +204,19 @@ proc foldOrg*(x: OrgBuilderResult): string =
   # echo acc.unsafeGet().tree[^1]
 
 when isMainModule:
-  let test1 = """* TODO Level 1
+  let test1 = """* TODO Level 1"""
-
-Some text inbetween
 
+  let test2 = """* TODO Level 1
+Foo
 ** DONE Level 2
 
 Some more content
 """
 
-  let acc = makeOrg(test1).foldOrg()
+  let test3 = """* TODO Level 1
-  echo acc
+Foo
+"""
+
+  let acc = makeOrg(test3).foldOrg()
+
+  discard acc

src/org/org_text_link.nim

@@ -7,7 +7,7 @@ import fp/[
   maybe,
   option,
 ]
-import ./org_builder
+import ./org_builder_api
 import ./org_types
 import ../utils/fp
 import ../parser/parser_internals

src/parser/parser_types.nim

@@ -330,10 +330,14 @@ proc foldBuilder*[T, T2](
 
 # -- Stringifiers
 
-proc `$`*(x: ParserToken): string =
+func pprint*(x: ParserToken): string =
-  &"""ParserToken(
+  let str = tokenStringValue(x)
-  value: {tokenStringValue(x)},
+  let escapedChar = if str == "\n": "\\n"
-)"""
+                    else: str
+  &"""ParserToken("{escapedChar}")
+"""
+
+func `$`*(x: ParserToken): string = pprint(x)
 
 const LEFT_HIGHLIGHT_CHAR = ">>"
 const RIGHT_HIGHLIGHT_CHAR = "<<"

src_v2/org/org_builder_api.nim

@@ -0,0 +1,79 @@
+import std/[
+  collections/sequtils,
+  strformat,
+  sugar,
+]
+import fp/[
+  resultM,
+]
+import ./org_types
+import ../parser/parser
+
+# -- OrgInlineBlock.Builder.Type
+
+type OrgInlineBuilderT* = OrgInlineBlock
+type OrgInlineBuilder* = Builder[OrgInlineBuilderT]
+type OrgInlineBuilderResult* = BuilderResult[OrgInlineBuilderT]
+
+# -- OrgInlineBlock.Builder.Initializers
+
+func initOrgInlineBuilder*(content: string): OrgInlineBuilderResult =
+  return OrgInlineBuilderResult.ok(OrgInlineBuilder((
+    parser: initParser(content),
+    tree: newSeq[OrgInlineBuilderT](),
+  )))
+
+func tokenizeInlineTokens*(kind: orgInlineBlockKind): seq[ParserToken] -> seq[OrgInlineBuilderT] =
+  return func(tokens: seq[ParserToken]): seq[OrgInlineBuilderT] =
+    return @[
+      OrgInlineBuilderT(
+        kind: kind,
+        content: tokens.tokensToString(),
+      )
+    ]
+
+func tokenizeRawText*(kind: orgInlineBlockKind): string -> OrgInlineBuilderT =
+  return func(content: string): OrgInlineBuilderT =
+    return OrgInlineBuilderT(
+      kind: kind,
+      content: content,
+    )
+
+# ## Blocks
+type OrgBuilderT* = OrgBlock
+type OrgBuilder* = Builder[OrgBuilderT]
+type OrgBuilderError* = BuilderError[OrgBuilderT]
+type OrgBuilderResult* = BuilderResult[OrgBuilderT]
+
+func initOrgBuilder*(content: string): OrgBuilderResult =
+  return OrgBuilderResult.ok(OrgBuilder((
+    parser: initParser(content),
+    tree: newSeq[OrgBuilderT](),
+  )))
+
+func pprint*(x: OrgBuilder): string =
+  &"""OrgBuilder(
+  parser: {x.parser}
+  tree: {x.tree}
+)"""
+
+func `$`*(x: OrgBuilder): string = pprint(x)
+
+func pprint*(x: OrgBuilderError): string =
+  &"""OrgBuilderError(
+  parser: {x.parser}
+  tree: {x.tree}
+)"""
+
+func `$`*(x: OrgBuilderError): string = pprint(x)
+
+# # proc orgBuilderConcat*(typeInfo: OrgBuilderT, concatFn: (ParserToken, OrgBuilderT) -> OrgBuilderT):
+# #                       (seq[ParserToken], OrgBuilderT) -> OrgBuilderT =
+# #   return proc(xs: seq[ParserToken], builder: OrgBuilderT): OrgBuilderT =
+# #     return xs.foldl(concatFn(b, a), typeInfo)
+
+
+# proc orgBuilderApply*(concatFn: (ParserToken, OrgBuilderT) -> OrgBuilderT):
+#   (seq[ParserToken], OrgBuilderT) -> OrgBuilderT =
+#     return proc(tokens: seq[ParserToken], builder: OrgBuilderT): OrgBuilderT =
+#       tokens.foldl(concatFn(b, a), builder)

src_v2/org/org_builder_heading.nim

@@ -0,0 +1,218 @@
+import std/[
+  collections/sequtils,
+  strformat,
+  strutils,
+  sugar,
+]
+import fp/[
+  option,
+  resultM,
+]
+import fusion/matching
+{.experimental: "caseStmtMacros".}
+import ./org_types
+import ./org_builder_api
+import ../parser/parser
+import ../utils/fp
+
+# -- Parsers
+
+let headingStarsParser* = following(@[
+  ignore(optional(newline)),
+  manyUntil(ch('*'), ch(' ')),
+  ignore(space)
+])
+
+proc createTodoKeywordParser(xs: seq[string]): parserFnT =
+  choice(xs.map((x: string) => str(x) + ignore(space)))
+
+let todoKeywords = @["TODO"]
+let doneKeywords = @["DONE"]
+
+let parseTodoKeyword = todoKeywords.createTodoKeywordParser()
+let parseDoneKeyword = doneKeywords.createTodoKeywordParser()
+
+# let parseContentText = @[
+#   anyUntil(choice(@[endOfStream, str("\n")])),
+# ]
+
+# let parseHeadlineNewline = @[
+#   choice(@[
+#     ch(NewLines),
+#     endOfStream,
+#   ])
+# ]
+
+# let parseHeadingText = @[
+#   anyUntil(newline),
+# ]
+
+# -- Tokenizers
+
+let buildStars = func(tokens: seq[ParserToken], org: OrgBlock): OrgBlock {.closure.}=
+  org.level = tokens.len
+  org
+
+# let buildTodo = func(tokens: seq[ParserToken], org: OrgBlock): OrgBlock {.closure.}=
+#   org.todo = tokens.tokensToString().some()
+#   org
+
+# let buildHeadlineContent = func(tokens: seq[ParserToken], org: OrgBlock): OrgBlock {.closure.}=
+#   let headlineString = tokens.tokensToString()
+
+#   let tokens = tryBuildInline(headlineString)
+#   .fold(
+#     x => newSeq[OrgInlineBuilderT](),
+#     (x: OrgInlineBuilder) => x.tree,
+#   )
+
+#   org.headlineContent = tokens
+#   org
+
+# let buildHeadlineChildren = func(tokens: seq[ParserToken], org: OrgBlock): OrgBlock {.closure.}=
+#   # let headlineString = tokens.tokensToString()
+
+#   org
+
+# let buildHeadlineNewline = func(tokens: seq[ParserToken], org: OrgBlock): OrgBlock {.closure.}=
+#   org
+
+proc tryBuildHeading(builder: OrgBuilderResult): OrgBuilderResult =
+  # echo builder
+  builder
+  .applyParsersSeqToSingle(
+    OrgBlock(kind: orgHeading),
+    @[
+      (parseHeadingStars, buildStars, false),
+
+      (@[optional(parseTodoKeyword)], buildTodo, true),
+      (@[optional(parseDoneKeyword)], buildTodo, true),
+
+      (parseHeadingText, buildHeadlineContent, false),
+
+      # (parseContentText, buildHeadlineChildren, true),
+
+      (parseHeadlineNewline, buildHeadlineNewline, false),
+    ]
+  )
+
+# let headingParser = choice(@[
+#   newline + ch('*'),
+#   endOfStream,
+# ])
+
+
+# let contentEndParser = newline
+
+# let buildNewline = func(tokens: seq[ParserToken], org: OrgBlock): OrgBlock {.closure.} =
+#   OrgBlock(
+#     kind: orgNewline
+#   )
+
+# proc concatOrgBlock(xs: seq[OrgBlock], ys: seq[OrgBlock]): seq[OrgBlock] = xs & ys
+
+# let parseBlockText = @[
+#   anyUntil(choice(@[endOfStream, str("\n")])),
+# ]
+
+# let contentParsersSeq: seq[tuple[
+#   parsers: seq[Parser -> ParserResult],
+#   tokenFoldFn: (seq[ParserToken], OrgBlock) -> OrgBlock,
+#   ignoreEmpty: bool,
+#   # concatFn: (seq[OrgBlock], seq[OrgBlock]) -> seq[OrgBlock],
+# ]] = @[
+#   (parseBlockText, buildNewline, true),
+#   (contentEndParser, buildNewline, true),
+# ]
+
+# proc parseHeadlineChildren(builder: OrgBuilder): OrgBuilderResult =
+#   var headingBlock = builder.tree[0]
+
+#   # echo "Builder " & $builder
+
+#   # var builderAcc: OrgBuilderResult = OrgBuilderResult.ok(builder)
+#   var builderAcc: OrgBuilderResult = OrgBuilderResult.ok(OrgBuilder(
+#     (
+#       parser: builder.parser,
+#       tree: @[],
+#   )
+#   ))
+
+#   echo "builderAcc before parse content ", builderAcc
+#   # echo builderAcc.tryParser(headingParser)
+#   while builderAcc.isOk() and builderAcc.tryParser(headingParser).isErr():
+#     builderAcc = builderAcc
+#       .applyParsersSeqToSeq(
+#         contentParsersSeq
+#       )
+#     echo "builderAcc after parse in while loop ", builderAcc
+#     # echo builderAcc
+
+
+#   let content = builderAcc.fold(
+#     (err) => 0, # newSeq[OrgBlock](),
+#     (builder: OrgBuilder) => len builder.tree,
+#   )
+
+#   # echo "builderAcc" & $builderAcc
+#   echo "content" & $content
+
+#   # headingBlock.content = content
+
+#   let res = builderAcc.fold(
+#     (err) => OrgBuilderResult.err((builder, "Could not parse content")),
+#     (builder: OrgBuilder) => OrgBuilderResult.ok((
+#         parser: builder.parser.emptyTokens(),
+#         tree: @[headingBlock],
+#     ))
+#   )
+
+#   res
+
+# proc makeOrg*(x: string): OrgBuilderResult =
+#   var acc = initOrgBuilder(x)
+
+#   while acc.isOk() and acc.tryParser(endOfStream).isErr():
+#     let unsafeAcc = acc.unsafeGet()
+
+#     let item = acc
+#     .tryBuildHeading()
+#     .flatMap(
+#       (x: OrgBuilder) => parseHeadlineChildren(x)
+#     )
+#     .flatMap(
+#       (x: OrgBuilder) => OrgBuilderResult.ok(OrgBuilder((
+#         parser: x.parser,
+#         tree: unsafeAcc.tree & x.tree,
+#       )))
+#     )
+
+#     acc = item
+
+#   acc
+
+# proc foldOrg*(x: OrgBuilderResult): string =
+#   x
+#   .fold(
+#     (err) => "Error" & $err,
+#     (builder: OrgBuilder) => $builder.tree,
+#   )
+#   # echo acc.unsafeGet().tree[^1]
+
+# when isMainModule:
+#   let test1 = """* TODO Level 1"""
+
+#   let test2 = """* TODO Level 1
+# Foo
+# ** DONE Level 2
+
+# Some more content
+# """
+
+#   let test3 = """* TODO Level 1
+# Foo
+# """
+
+#   let acc = makeOrg(test3).foldOrg()
+
+#   discard acc

src_v2/org/org_builder_inline_text.nim

@@ -0,0 +1,101 @@
+import std/[
+  collections/sequtils,
+  sugar,
+]
+import fp/[
+  option,
+  resultM,
+]
+import ./org_types
+import ./org_builder_api
+import ./org_builder_link.nim
+import ../parser/parser
+
+# -- Parsers
+
+let boldParser* =             anyBetweenPair(ch('*'))
+let italicParser* =           anyBetweenPair(ch('/'))
+let underlineParser* =        anyBetweenPair(ch('_'))
+let verbatimParser* =         anyBetweenPair(ch('='))
+let codeParser* =             anyBetweenPair(ch('~'))
+let strikeThroughParser* =    anyBetweenPair(ch('+'))
+
+# -- Tokenizers
+
+let rawTextTokenizer* =       tokenizeRawText(orgRawText)
+
+let boldTokenizer* =          tokenizeInlineTokens(orgBoldText)
+let italicTokenizer* =        tokenizeInlineTokens(orgItalicText)
+let underlineTokenizer* =     tokenizeInlineTokens(orgUnderlineText)
+let verbatimTokenizer* =      tokenizeInlineTokens(orgVerbatimText)
+let codeTokenizer* =          tokenizeInlineTokens(orgCodeText)
+let strikeThroughTokenizer* = tokenizeInlineTokens(orgStrikeThroughText)
+
+let styledTextTokenizers* = @[
+  (boldParser,          boldTokenizer),
+  (italicParser,        italicTokenizer),
+  (underlineParser,     underlineTokenizer),
+  (verbatimParser,      verbatimTokenizer),
+  (codeParser,          codeTokenizer),
+  (strikeThroughParser, strikeThroughTokenizer),
+  (linkParser,          linkTokenizer),
+]
+
+proc tryTokenizeRawText*(tokens: seq[ParserToken]): seq[OrgInlineBuilderT] =
+  ## Merge all parser `tokens` into a string to tokenize for the builder.
+  ## Unless the string is empty, in this case return an empty list.
+  let str = tokens.foldl(a & b.toString(), "")
+  if str.len == 0: @[]
+  else: @[rawTextTokenizer(str)]
+
+proc tryTokenizeInline*(content: string): OrgInlineBuilderResult =
+  initOrgInlineBuilder(content)
+  .flatMap((builder: OrgInlineBuilder) => tryTokenize(
+    builder = builder,
+    builderFns = styledTextTokenizers,
+    defaultTokenizerFn = tryTokenizeRawText,
+  ))
+
+# -- Tests
+
+when isMainModule:
+  import fp/list
+
+  block testParsers:
+    proc testParser(str: string, parser: parserFnT): string =
+      initParserResult(str).flatMap(parser).tokensToString()
+
+    assert testParser("*bold*", boldParser) == "bold"
+    assert testParser("/italic/", italicParser) == "italic"
+    assert testParser("_underline_", underlineParser) == "underline"
+    assert testParser("=verbatim=", verbatimParser) == "verbatim"
+    assert testParser("~code~", codeParser) == "code"
+    assert testParser("+strikeThrough+", strikeThroughParser) == "strikeThrough"
+
+  block testTokenizers:
+    let testStr = "Regular *bold* [[placeholder.com]] /italic/ _underline_ =verbatim= ~code~ +strikethrough+ [[https://placeholder.com][title]]"
+    let testBuilder = tryTokenizeInline(testStr)
+
+    assert testBuilder.isOk()
+
+    let testTokens = testBuilder.unsafeGet().tree
+    let testTokensEpxected = @[
+      OrgInlineBlock(kind: orgRawText, content: "Regular "),
+      OrgInlineBlock(kind: orgBoldText, content: "bold"),
+      OrgInlineBlock(kind: orgRawText, content: " "),
+      OrgInlineBlock(kind: orgLink, linkUrl: "placeholder.com"),
+      OrgInlineBlock(kind: orgRawText, content: " "),
+      OrgInlineBlock(kind: orgItalicText, content: "italic"),
+      OrgInlineBlock(kind: orgRawText, content: " "),
+      OrgInlineBlock(kind: orgUnderlineText, content: "underline"),
+      OrgInlineBlock(kind: orgRawText, content: " "),
+      OrgInlineBlock(kind: orgVerbatimText, content: "verbatim"),
+      OrgInlineBlock(kind: orgRawText, content: " "),
+      OrgInlineBlock(kind: orgCodeText, content: "code"),
+      OrgInlineBlock(kind: orgRawText, content: " "),
+      OrgInlineBlock(kind: orgStrikeThroughText, content: "strikethrough"),
+      OrgInlineBlock(kind: orgRawText, content: " "),
+      OrgInlineBlock(kind: orgLink, linkDescription: "title".some(), linkUrl: "https://placeholder.com"),
+    ]
+
+    assert testTokens.asList() == testTokensEpxected.asList()

src_v2/org/org_builder_link.nim

@@ -0,0 +1,89 @@
+import std/[
+  collections/sequtils,
+  strformat,
+  sugar,
+]
+import fp/[
+  option,
+  resultM,
+]
+import ./org_types
+import ./org_builder_api
+import ../parser/parser
+import ../utils/fp
+
+import fusion/matching
+{.experimental: "caseStmtMacros".}
+
+# -- Parsers
+
+let linkStartParser* = following(@[
+  ignore(str("[[")),
+  anyUntil(choice(@[str("]["), str("]]")])),
+  optional(ignore(str("][")))
+])
+let linkEndParser* = following(@[
+  anyUntil(str("]]")),
+  ignore(str("]]")),
+])
+
+let linkParser* = proc(parser: Parser): ParserResult {.closure.} =
+  # Parse an an org link in the `parser` state.
+  # Return two tokens for a link with description: [[url][description]]
+  # Return one token for a link without description : [[url]]
+  let linkUrl = linkStartParser(parser)
+  .map(flattenTokens)
+
+  let linkValue = linkUrl
+  .map(emptyTokens)
+  .flatMap(linkEndParser)
+  .map(flattenTokens)
+
+  case (linkUrl, linkValue):
+    of (Some(@key), Some(@value)):
+      ParserResult.ok(
+        Parser(
+          state: value.state,
+          tokens: @[
+            key.tokens[0],
+            value.tokens[0],
+          ],
+        )
+      )
+    else:
+      linkValue
+
+# -- Tokenizers
+
+func linkStringifier*(linkUrl: string, linkDescription: Option[string]): string =
+  case (linkUrl, linkDescription):
+    of (@linkUrl, Some(@linkDescription)):
+       return &"[[{linkUrl}][{linkDescription}]]"
+    of (@linkUrl, None()):
+       return &"[[{linkUrl}]]"
+
+let linkTokenizer* = func(parserTokens: seq[ParserToken]): seq[OrgInlineBuilderT] {.closure.} =
+  [@linkUrl, @linkDescription] := parserTokens.map(toString)
+  let linkDescriptionOption = linkDescription.some().notEmpty()
+  return @[
+    OrgInlineBuilderT(
+      kind: orgLink,
+      content: linkStringifier(linkUrl, linkDescriptionOption),
+      linkUrl: linkUrl,
+      linkDescription: linkDescriptionOption,
+    )
+  ]
+
+when isMainModule:
+  block testParsers:
+    proc testParser(str: string, parser: parserFnT): string =
+      initParserResult(str).flatMap(parser).tokensToString()
+
+    assert testParser("[[placeholder.com]]", linkParser) == "placeholder.com"
+    assert testParser("[[placeholder.com][ - title]]", linkParser) == "placeholder.com - title"
+
+    # .linkParser()
+    # .foldTokens(
+    #   onError = xs => newSeq[OrgInlineBuilderT](),
+    #   onSuccess = linkTokenizer,
+    # )

src_v2/org/org_builder_paragraph.nim

@@ -0,0 +1,138 @@
+import std/[
+  collections/sequtils,
+  sugar,
+]
+import fp/[
+  option,
+  resultM,
+]
+import ./org_types
+import ./org_builder_api
+import ./org_builder_link
+import ./org_builder_inline_text
+import ../parser/parser
+import ../utils/fp
+
+import fusion/matching
+{.experimental: "caseStmtMacros".}
+
+# let lineTokenizer = (builder: OrgInlineBuilder) => tryTokenize(
+#     builder = builder,
+#     builderFns = styledTextTokenizers,
+#     defaultTokenizerFn = tryTokenizeRawText,
+#   )
+
+# OrgDocucment
+
+# -> Seq [Builder -> Builder]
+
+# One of OrgBlock
+
+# @[
+
+#     OrgBuilderResult -> OrgBuilderResult
+# ]
+# with default OrgBuilder -> OrgBuilder
+# until Eol
+
+let lineParser = anyUntil(newlineOrEol)
+
+let listTypesParser = choice(@[
+  ch('-'),
+  ch('+'),
+  choice(@[letter, digit]) + choice(@[ch('.'), ch(')')]),
+])
+
+let listStartParser = manyUntil(space, listTypesParser)
+let listTypeParser = listTypesParser + ignore(space)
+let listContentParser = anyUntil(newlineOrEol) + ignore(newlineOrEol)
+
+let buildListItem = proc(builder: OrgBuilder): OrgBuilderResult {.closure.} =
+  let (parser, tree) = builder
+
+  let beforeSpaces = ParserResult.ok(parser)
+  .flatMap(listStartParser)
+  .map(flattenTokens)
+
+  let listType = beforeSpaces
+  .map(emptyTokens)
+  .flatMap(listTypeParser)
+  .map(flattenTokens)
+
+  let listContent = listType
+  .map(emptyTokens)
+  .flatMap(listContentParser)
+  .map(flattenTokens)
+
+  case (beforeSpaces, listType, listContent):
+    of (Some(@space), Some(@symbol), Some(@content)):
+      let treeResult = tree &
+        OrgBlock(
+          kind: orgList,
+          listIndentation: 1,
+          listBulletType: '-',
+          listContent: tryTokenizeInline(content.tokens.tokensToString()).unsafeGet().tree
+        )
+
+      OrgBuilderResult.ok(OrgBuilder((
+        parser: content,
+        tree: treeResult,
+      )))
+    else: OrgBuilderResult.err(OrgBuilderError(
+      kind: parserError,
+      parser: listContent,
+      tree: tree,
+    ))
+
+proc buildParagraph*(
+  builder: OrgBuilder,
+  builderFns: seq[proc (builder: OrgBuilder): OrgBuilderResult],
+  stopAtParserFn = endOfStream,
+): OrgBuilderResult =
+
+  var builderAcc: OrgBuilderResult = OrgBuilderResult.ok(builder)
+
+  while builderAcc.isOk() and builderAcc.tryParserResult(stopAtParserFn).isErr():
+    var found = false
+
+    for builderFn in builderFns:
+      # let (builderFn) = fn
+      let builderResult: OrgBuilderResult = builderAcc.flatMap(builderFn)
+
+      if builderResult.isOk():
+        found = true
+        builderAcc = builderResult
+        break
+
+    if not found:
+      builderAcc
+      .flatMap((builder: OrgBuilder) => tryTokenize(
+        builder = builder,
+        builderFns = styledTextTokenizers,
+        defaultTokenizerFn = tryTokenizeRawText,
+      ))
+      .fold(
+        OrgInlineBuilder
+      )
+
+
+      builderAcc = OrgBuilderResult.err(OrgBuilderError(
+        kind: builderError,
+        parser: builderAcc.fold(
+          (err: OrgBuilderError) => err.parser,
+          (builder: OrgBuilder) => ParserResult.ok(builder.parser),
+        ),
+        tree: builder.tree,
+      ))
+      break
+
+  builderAcc
+
+let paragraphBuilders: seq[proc (builder: OrgBuilder): OrgBuilderResult] = @[buildListItem]
+
+when isMainModule:
+  block testParsers:
+    let test = initOrgBuilder("""- List item
+1. List item
+random stuff""").flatMap((builder: OrgBuilder) => builder.buildParagraph(paragraphBuilders))
+    echo test

src_v2/org/org_types.nim

@@ -0,0 +1,249 @@
+import std/[
+  sequtils,
+  strutils,
+  sugar,
+]
+import fp/[
+  option,
+]
+import fusion/matching
+import ../utils/printers
+
+{.experimental: "caseStmtMacros".}
+
+# -- OrgInlineBlock.Type
+
+type
+  orgInlineBlockKind* = enum
+    orgRawText,
+    orgText,
+
+    # Formating
+    orgBoldText,
+    orgItalicText,
+    orgUnderlineText,
+    orgVerbatimText,
+    orgCodeText,
+    orgStrikeThroughText,
+
+    # Links
+    orgLink,
+
+  OrgInlineBlock* = ref object
+    children*: seq[OrgInlineBlock]
+    content*: string
+
+    case kind*: orgInlineBlockKind
+    of orgRawText: discard
+    of orgText: discard
+
+    # Formating
+    of orgBoldText: discard
+    of orgItalicText: discard
+    of orgUnderlineText: discard
+    of orgVerbatimText: discard
+    of orgCodeText: discard
+    of orgStrikeThroughText: discard
+
+    # Links
+    of orgLink:
+      linkUrl*: string
+      linkDescription*: Option[string]
+
+
+# OrgInlineBlock.Equals
+
+func `==`*(a: OrgInlineBlock, b: OrgInlineBlock): bool =
+  ## Compare two `OrgInlineBlock` objects.
+  ## TODO Compare children
+
+  if (a.kind != b.kind): return false
+
+  case ((a.kind, b.kind)):
+    of((orgLink, orgLink)):
+      a.linkUrl == b.linkUrl and a.linkDescription == b.linkDescription
+
+    else: a.content == b.content
+
+# -- OrgInlineBlock.PrettyPrinters
+
+proc `$`*(x: orgInlineBlockKind): string =
+  case x:
+    of orgRawText:            "Text (Raw)"
+    of orgText:               "Text"
+
+    # Formating
+    of orgBoldText:           "Text (Bold)"
+    of orgItalicText:         "Text (Italic)"
+    of orgUnderlineText:      "Text (Underline)"
+    of orgVerbatimText:       "Text (Verbatim)"
+    of orgCodeText:           "Text (Code)"
+    of orgStrikeThroughText:  "Text (StrikeThrough)"
+
+    # Links
+    of orgLink: "Link"
+
+const PPRINT_INDENT_SIZE* = 2
+
+func pprint*(x: OrgInlineBlock, indent = 0): string =
+  let specialFields = case x.kind:
+    of orgLink:
+      @[
+        ("linkUrl", $x.linkUrl, true),
+        ("linkDescription", x.linkDescription.getOrElse(""), x.linkDescription.isSome()),
+      ]
+    else: @[]
+
+  let fields = @[
+    ("kind", $x.kind, true),
+    ("content", $x.content, x.content.len != 0),
+  ]
+  .concat(specialFields)
+  .stringifyFields()
+
+  stringifyBlock(
+    "OrgInlineBlock",
+    indent,
+    fields,
+  )
+
+func `$`*(x: OrgInlineBlock): string = pprint(x)
+
+func pprint*(xs: seq[OrgInlineBlock], indent = 0): string =
+  stringifySeq(xs, (x: OrgInlineBlock) => pprint(x, indent), indent)
+
+func `$`*(xs: seq[OrgInlineBlock]): string = pprint(xs)
+
+## -- OrgBlock.Type
+
+type
+  orgBlockKind* = enum
+    orgHeading
+    orgParagraph
+    orgList
+    orgNewline
+  OrgBlock* = ref object
+    children*: seq[OrgInlineBlock]
+
+    case kind*: orgBlockKind
+    of orgHeading:
+      level*: int
+      todo*: Option[string]
+      headlineContent*: seq[OrgInlineBlock]
+      content*: seq[OrgBlock]
+    of orgParagraph:
+      paragraphContent: seq[OrgInlineBlock]
+    of orgList:
+      listIndentation*: int
+      listBulletType*: char
+      listContent*: seq[OrgInlineBlock]
+    of orgNewline: discard
+
+## -- OrgBlock.PrettyPrinters
+
+func pprint*(x: OrgBlock, indent = 0): string =
+  let fields = case x.kind:
+    of orgHeading:
+      @[
+        ("kind", $x.kind, true),
+        ("level", $x.level, true),
+        ("todo", $x.todo, x.todo.isSome()),
+        ("headlineContent", $x.headlineContent, x.headlineContent.len != 0),
+        ("children", $x.children, x.children.len != 0),
+        (
+          "content",
+          ("@[\n" &
+            x.content.map((x) => pprint(x)).join(",\n").indent(PPRINT_INDENT_SIZE) &
+            ",\n],"
+          ).indent(indent),
+          x.content.len != 0
+        ),
+      ]
+    of orgParagraph:
+      @[
+        ("kind", $x.kind, true),
+        ("paragraphContent", $x.paragraphContent, x.paragraphContent.len != 0),
+      ]
+    of orgList:
+      @[
+        ("kind", $x.kind, true),
+        ("listContent", $x.listContent, x.listContent.len != 0),
+        ("listIndentation", $x.listIndentation, true),
+        ("listBulletType", $x.listBulletType, true),
+      ]
+    else:
+      @[
+        ("kind", $x.kind, true),
+      ]
+
+  stringifyBlock(
+    "OrgBlock",
+    indent,
+    fields.stringifyFields(),
+  )
+
+func `$`*(x: OrgBlock): string = pprint(x)
+
+func pprint*(xs: seq[OrgBlock], indent = 0): string =
+  stringifySeq(xs, (x: OrgBlock) => pprint(x, indent), indent)
+
+func `$`*(xs: seq[OrgBlock]): string = pprint(xs)
+
+# -- OrgDocument.Type
+
+type
+  OrgDocument* = ref object
+    children*: seq[OrgBlock]
+
+# -- OrgDocument.PrettyPrinters
+
+func pprint*(x: OrgDocument, indent = 0): string =
+  let fields = @[
+    ("children", $x.children, true),
+  ]
+  .stringifyFields()
+
+  stringifyBlock(
+    "OrgDocument",
+    indent,
+    fields,
+  )
+
+func `$`*(xs: OrgDocument): string = pprint(xs)
+
+when isMainModule:
+
+  block testOrgInlineBlockEquals:
+    assert OrgInlineBlock(kind: orgRawText) == OrgInlineBlock(kind: orgRawText)
+    assert OrgInlineBlock(kind: orgRawText, content: "") == OrgInlineBlock(kind: orgRawText, content: "")
+    assert OrgInlineBlock(kind: orgRawText, content: "a") != OrgInlineBlock(kind: orgRawText, content: "b")
+    assert OrgInlineBlock(kind: orgRawText) != OrgInlineBlock(kind: orgBoldText)
+    # Link
+    assert OrgInlineBlock(kind: orgLink, linkDescription: "desc".some(), linkUrl: "url") == OrgInlineBlock(kind: orgLink, linkDescription: "desc".some(), linkUrl: "url")
+    assert OrgInlineBlock(kind: orgLink, linkUrl: "url") != OrgInlineBlock(kind: orgLink, linkDescription: "desc".some(), linkUrl: "url")
+
+  # let doc = OrgDocument(
+  #   children: @[
+  #     OrgBlock(
+  #       kind: orgHeading,
+  #       children: @[
+  #         OrgInlineBlock(
+  #           kind: orgLink,
+  #           linkUrl: "https://placeholder.com",
+  #           linkDescription: "Placeholder".some(),
+  #         ),
+  #       ],
+  #       content: @[
+  #         OrgBlock(
+  #           kind: orgNewline,
+  #         ),
+  #         OrgBlock(
+  #           kind: orgNewline,
+  #         )
+  #       ],
+  #     ),
+  #     OrgBlock(kind: orgHeading, level: 1),
+  #     OrgBlock(kind: orgHeading),
+  #   ]
+  # )
+  # echo doc

src_v2/org/test.nim

@@ -0,0 +1,3 @@
+import experimental/diff
+
+echo diff(@[1,2,3], @[1,2,3])

src_v2/parser/builder_api.nim

@@ -0,0 +1,119 @@
+import std/[
+  collections/sequtils,
+  options,
+  strformat,
+  strutils,
+  sugar,
+]
+import fp/[
+  resultM
+]
+import ./builder_types
+import ./parser_types
+import ./parser_api
+
+# -- Builder API
+
+proc tryTokenize*[T](
+  builder: Builder[T],
+  builderFns: seq[tuple[
+    parserFn: parserFnT,
+    tokenizerFn: seq[ParserToken] -> seq[T],
+  ]],
+  defaultTokenizerFn: seq[ParserToken] -> seq[T],
+  stopAtParserFn = newlineOrEol,
+  concatTokensFn = concat[T],
+): BuilderResult[T] =
+  ## Try to tokenize text in `builder` by checking `builderFns` seq for a sucessful `parserFn`.
+  ## When a `parserFn.ok` is found, tokenize the text in the `Parser` using the current tokenizerFn
+  ## and merge the result into `builder.tree` using the `concatTokensFn`.
+  ## When no parser matches, tokenize with the `defaultTokenizerFn` until `stopAtParserFn is matched.
+
+  let (parser, tree) = builder
+  # Mutating accumulators
+  var parserAcc: ParserResult = ParserResult.ok(parser)
+  var builderAcc: Builder[T] = builder
+
+  while parserAcc.isOk() and parserAcc.flatMap(stopAtParserFn).isErr():
+    # Empty the parser tokens as we want to seperate them for the next parser in the sequence
+    let emptyParser = parserAcc.map(emptyTokens)
+
+    # Find the a parser and convert its tokens with the `tokenizerFn`
+    var found = false
+    for fn in builderFns:
+      let (parserFn, tokenizerFn) = fn
+
+      let parseResult = emptyParser.flatMap(parserFn)
+      if parseResult.isOk():
+        found = true
+
+        # Convert all previous unmatched tokens via the `defaultTokenizerFn`
+        let defaultBuilderTokens = parserAcc
+        .foldTokens(
+          onErrorFn = _ => newSeq[T](),
+          onSuccessFn = defaultTokenizerFn,
+        )
+
+        let okParser = parseResult.unsafeGet()
+        parserAcc = parseResult.map(emptyTokens)
+        builderAcc = initBuilder(
+          okParser,
+          concatTokensFn(
+            builderAcc.tree,
+            defaultBuilderTokens,
+            tokenizerFn(okParser.tokens),
+          )
+        )
+        break
+
+    if not found:
+      parserAcc = parserAcc.flatMap(anyCh)
+
+  let defaultBuilderTokens = parserAcc
+  .foldTokens(
+    onErrorFn = _ => newSeq[T](),
+    onSuccessFn = defaultTokenizerFn,
+  )
+
+  BuilderResult[T].ok(initBuilder(
+    builderAcc.parser,
+    concatTokensFn(
+      builderAcc.tree,
+      defaultBuilderTokens,
+    ),
+  ))
+
+# -- Stringifiers
+
+func pprint[T](x: Builder): string =
+  &"""Builder()
+  """
+
+when isMainModule:
+  type TestStringBuilderT* = string
+  type TestStringBuilder* = Builder[TestStringBuilderT]
+  type TestStringBuilderResult* = BuilderResult[TestStringBuilderT]
+
+  block testApi:
+    let testParensParser = anyBetween(str(" ("), str(") "))
+
+    proc testDefaultTokenizer(tokens: seq[ParserToken]): seq[string] {.closure.} =
+      @[tokens.toString()]
+    proc testParensTokenizer(tokens: seq[ParserToken]): seq[string] {.closure.} =
+      @[&"Parens({tokens.toString()})"]
+
+    let testBuilder = initBuilder(
+      initParser("""sentence (with parens) and more
+And ignore this part"""),
+      newSeq[TestStringBuilderT]()
+    )
+    .tryTokenize(
+      builderFns = @[(
+        testParensParser,
+        testParensTokenizer
+      )],
+      defaultTokenizerFn = testDefaultTokenizer,
+    )
+
+    assert testBuilder.isOk() == true
+    assert testBuilder.unsafeGet().tree == @["sentence", "Parens(with parens)", "and more"]

src_v2/parser/builder_types.nim

@@ -0,0 +1,96 @@
+import std/[
+  sugar,
+]
+import fp/[
+  resultM,
+]
+import ./parser_types
+import ./parser_api
+
+type
+  Builder*[T] = tuple[
+    parser: Parser,
+    tree: seq[T]
+  ]
+  builderErrorKind* = enum
+    parserError
+    builderError
+  BuilderError*[T] = ref object
+    kind*: builderErrorKind
+    parser*: ParserResult
+    tree*: seq[T]
+  BuilderResult*[T] = Result[Builder[T], BuilderError[T]]
+
+# -- Initalizers
+
+proc initBuilder*[T](parser: Parser, tree: seq[T]): Builder[T] =
+  Builder[T]((
+    parser,
+    tree
+  ))
+
+# -- Modifiers
+
+proc setParser*[T](builder: Builder[T], parser: Parser): Builder[T] =
+  Builder[T]((
+    parser,
+    builder.tree,
+  ))
+
+proc setTree*[T](builder: Builder[T], tree: seq[T]): Builder[T] =
+  Builder[T]((
+    builder.parser,
+    tree,
+  ))
+
+proc tryParser*[T](
+  builder: Builder[T],
+  parserFn: parserFnT,
+): BuilderResult[T] =
+  ## Try out a `parser` on a `builder`
+  ## When successful return the original builder, otherwise return an error
+  let parser = ParserResult
+  .ok(Parser(
+    state: builder.parser.state,
+    tokens: @[],
+  ))
+  .flatMap(parserFn)
+
+  parser
+  .foldTokens(
+    (err: ParserError) => BuilderResult[T].err(BuilderError[T](
+      kind: parserError,
+      parser: parser,
+      tree: builder.tree,
+    )),
+    (newTokens: seq[ParserToken]) => BuilderResult[T].ok(builder),
+  )
+proc tryParserResult*[T](
+  builder: BuilderResult[T],
+  parser: Parser -> ParserResult,
+): BuilderResult[T] =
+  ## Try out a `parser` on a `builder` result
+  ## When succesful return the ok builder, otherwise return an error
+  builder.flatMap((x: Builder[T]) => tryParser(x, parser))
+
+when isMainModule:
+  type TestStringBuilderT* = string
+  type TestStringBuilder* = Builder[TestStringBuilderT]
+  type TestStringBuilderResult* = BuilderResult[TestStringBuilderT]
+
+  let testBuilder123 = initBuilder(
+    initParser("123"),
+    newSeq[TestStringBuilderT]()
+  )
+
+  block testModifiers:
+    # setters
+    assert testBuilder123.setParser(initParser("abc")).parser.state.stream == "abc"
+    assert testBuilder123.setTree(@["abc"]).tree[0] == "abc"
+
+    # tryParser
+    assert testBuilder123.tryParser(ch('1')).isOk() == true
+    assert testBuilder123.tryParser(ch('2')).isErr() == true
+
+  # echo testBuilder123
+  # block testModifiers:

src_v2/parser/parser.nim

@@ -0,0 +1,9 @@
+import parser_types
+import parser_api
+import builder_types
+import builder_api
+
+export parser_types
+export parser_api
+export builder_types
+export builder_api

src_v2/parser/parser_api.nim

@@ -0,0 +1,401 @@
+import std/[
+  options,
+  strutils,
+  strformat,
+  collections/sequtils,
+  sugar,
+]
+import fp/[
+  maybe,
+  resultM,
+]
+import ../utils/str
+import ./parser_types
+
+# -- Utilities
+
+proc isStreamCompleted*(parser: Parser): bool =
+  ## Check if the `parser` index is at/over the stream length.
+  parser.state.position >= parser.state.stream.len - 1
+
+proc isStreamCompleted*(parserResult: ParserResult): bool =
+  ## Check if the `parserResult.state` index is at/over the stream length.
+  parserResult.fold(
+    err => false,
+    isStreamCompleted,
+  )
+
+# -- Parsing functions
+
+proc ch*(expectedChars: set[char]): parserFnT {.inline.} =
+  ## Create parser function with set of `expectedChar`.
+  ## When the parser has the character set at the following index return `ParserResult.ok`.
+  return proc(parser: Parser): ParserResult =
+    let state = parser.state
+    let newIndex = state.position + 1
+
+    if newIndex > (state.stream.len - 1):
+      return err(ParserError(
+        kind: endOfStringErr,
+        expected: expectedChars.prettyExpectedSet(),
+        index: newIndex,
+        parser: parser,
+      ))
+    else:
+      let foundChar = state.stream[newIndex]
+      if foundChar in expectedChars:
+        return Parser(
+          state: ParserState(
+            stream: state.stream,
+            position: newIndex,
+            lastPosition: parser.state.position,
+          ),
+          tokens: parser.tokens & initParserToken(foundChar)
+        ).ok()
+      else:
+        return err(ParserError(
+          kind: charMismatchErr,
+          unexpected: $foundChar,
+          expected: expectedChars.prettyExpectedSet(),
+          index: newIndex,
+          parser: parser,
+        ))
+
+proc ch*(expectedChar: char): parserFnT {.inline.} =
+  ## Creates parser function with `expectedChar`
+  ## When the parser has the character at the following index return `ParserResult.ok`
+  return proc(parser: Parser): ParserResult =
+    let state = parser.state
+    let newIndex = state.position + 1
+
+    if newIndex > (state.stream.len - 1):
+      return err(ParserError(
+        kind: endOfStringErr,
+        expected: &"{expectedChar}",
+        index: newIndex,
+        parser: parser,
+      ))
+    else:
+      let foundChar = state.stream[newIndex]
+      if expectedChar == foundChar:
+        return Parser(
+          state: ParserState(
+            stream: state.stream,
+            position: newIndex,
+            lastPosition: parser.state.position,
+          ),
+          tokens: parser.tokens & initParserToken(foundChar)
+        ).ok()
+      else:
+        return err(ParserError(
+          kind: charMismatchErr,
+          unexpected: &"{foundChar}",
+          expected: &"{expectedChar}",
+          index: newIndex,
+          parser: parser,
+        ))
+
+let anyCh* = ch(AllChars)
+let digit* = ch(Digits)
+let letter* = ch(Letters)
+let space* = ch(' ')
+let whitespace* = ch(Whitespace)
+let newline* = ch(Newlines)
+
+proc str*(expectedString: string): parserFnT {.inline.} =
+  ## Creates parser function with `expectedString`
+  ## When the parser has the string at the following index return `ParserResult.ok`
+  return proc(parser: Parser): ParserResult =
+    var res: ParserResult = parser.ok()
+    for c in expectedString.items:
+      if res.isErr: break
+      res = res.flatMap(ch(c))
+    return res
+
+proc startOfStream*(parser: Parser): ParserResult =
+  ## Check if the following character is the end of the stream.
+  ## Errors when the end of stream was already reached.
+  let position = parser.state.position
+
+  if position == 0 or position == -1:
+    ok(parser)
+  else:
+    err(ParserError(
+      kind: startOfStringErr,
+      expected: "startOfStream",
+      index: position,
+      parser: parser,
+    ))
+
+proc endOfStream*(parser: Parser): ParserResult =
+  ## Check if the following character is the end of the stream.
+  ## Errors when the end of stream was already reached.
+  let state = parser.state
+  let newIndex = state.position + 1
+
+  if newIndex == parser.state.stream.len:
+    ok(parser)
+  elif newIndex > parser.state.stream.len:
+    return err(ParserError(
+      kind: endOfStringErr,
+      expected: "endOfStream",
+      index: newIndex,
+      parser: parser,
+    ))
+  else:
+    let foundChar = state.stream[newIndex]
+    err(ParserError(
+      kind: charMismatchErr,
+      unexpected: $foundChar,
+      expected: "endOfStream",
+      index: newIndex,
+      parser: parser,
+    ))
+
+# -- Parsing API
+
+proc plus*(parserFnA: parserFnT, parserFnB: parserFnT): parserFnT {.inline.} =
+  ## Creates parser function with combining two parser functions `parserFnA` plus `parserFnB`
+  return proc(parser: Parser): ParserResult =
+    parserFnA(parser).flatMap(parserFnB)
+
+proc `+`*(parserFnA: parserFnT, parserFnB: parserFnT): parserFnT {.inline.} =
+  ## Creates infix parser function with combining two parser functions `parserFnA` plus `parserFnB`
+  return proc(parser: Parser): ParserResult =
+    parserFnA(parser).flatMap(parserFnB)
+
+proc optional*(parserFn: parserFnT): parserFnT {.inline.} =
+  ## Creates parser function with a nested `parserFn`:
+  ## Continues on succesful parser
+  ## Ignores failing parsers
+  return proc(parser: Parser): ParserResult =
+    let newParser = parserFn(parser)
+    if newParser.isOk():
+      newParser
+    else:
+      parser.ok()
+
+proc ignore*(parserFn: parserFnT): parserFnT {.inline.} =
+  ## Creates parser function with a nested `parserFn`:
+  ## Parses using the `parserFn` but dont capture the resulting tokens.
+  return proc(parser: Parser): ParserResult =
+    return parserFn(parser)
+    .map((x: Parser) => Parser(
+      state: x.state,
+      tokens: parser.tokens,
+    ))
+
+proc peek*(amount: int, parserFn: parserFnT): parserFnT {.inline.} =
+  ## Creates parser function with a nested `parserFn`:
+  ## Parses using the `parserFn` but dont capture the resulting tokens and keep the current position.
+  return proc(parser: Parser): ParserResult =
+    let state = parser.state
+    let newIndex = state.position + amount
+
+    let newParser = initParser(
+      stream = state.stream,
+      tokens = parser.tokens,
+      position = newIndex,
+      lastPosition = state.position,
+    )
+
+    parserFn(newParser)
+    .map(p => parser)
+
+proc peek1*(parserFn: parserFnT): parserFnT = peek(1, parserFn)
+proc peekCurrent*(parserFn: parserFnT): parserFnT = peek(0, parserFn)
+proc peekBack1*(parserFn: parserFnT): parserFnT = peek(-1, parserFn)
+
+proc manyUntil*(acceptFn: parserFnT, stopFn: parserFnT): parserFnT {.inline.} =
+  ## Creates parser function with a nested `acceptFn` parser function until the `stopFn` parserFunction is met:
+  ## Parses until the `stopFn` is reached or on an errror.
+  return proc(parser: Parser): ParserResult =
+    var res: ParserResult = parser.ok()
+    while res.isOk() and res.flatMap(stopFn).isErr():
+      res = res.flatMap(acceptFn)
+    return res
+
+proc anyUntil*(stopFn: parserFnT): parserFnT {.inline.} =
+  ## Parses any character until the `stopFn` is reached or on an errror.
+  ## Needs at least one character match.
+  manyUntil(anyCh, stopFn)
+
+proc choice*(parserFns: seq[parserFnT]): parserFnT {.inline} =
+  ## creates parser function that checks any of the `parserFns`.
+  ## Needs one match for a `ParserResult.ok`.
+  return proc(parser: Parser): ParserResult {.closure.} =
+    var errors: seq[ParserResult] = newSeq[ParserResult]()
+    var found = Nothing[ParserResult]()
+
+    for fn in parserFns:
+      let fnResult: ParserResult = fn(parser)
+
+      if fnResult.isOk():
+        found = fnResult.just
+        break
+      else:
+        errors = errors & fnResult
+
+    return found
+    .fold(
+      proc(): ParserResult =
+        let prettyErrors = errors.map((x: ParserResult) => x.error().expected)
+        err(ParserError(
+          kind: choiceMismatchErr,
+          index: parser.state.position + 1,
+          expected: &"Choice ({prettyErrors})",
+          unexpected: errors[0].error().unexpected,
+          parser: parser,
+        )),
+      proc(x: ParserResult): ParserResult = x,
+    )
+
+proc following*(parserFns: seq[parserFnT]): parserFnT {.inline.} =
+  ## Checks a sequence of `parserFns`.
+  ## All of them need to be `ParserResult.ok`
+  return proc(parser: Parser): ParserResult {.closure.} =
+    parserFns.foldl(a.flatMap(b), parser.ok)
+
+proc between*(startParserFn: parserFnT, stopParserFn: parserFnT): parserFnT -> parserFnT {.inline.} =
+  ## Creates parser function with that matches a `parserFn` between `startParserFn` and `stopParserFn`.
+  ## Ignores the delimiters in the tokens.
+  ## Example:
+  ##   between(ch('('), ch(')'))(str("abc")) => Matches (abc)
+  return proc(parserFn: parserFnT): parserFnT {.closure.} =
+    ignore(startParserFn) + parserFn + ignore(stopParserFn)
+
+let betweenPair* = proc(delimiterParserFn: parserFnT): parserFnT -> parserFnT {.inline.} =
+  ## Creates parser function with that matches anything between matching `delimiterParserFn`
+  ## Ignores the delimiters in the tokens.
+  ## Example:
+  ##   betweenPair(ch('"')(str("abc"))) => Matches "abc"
+  return proc(parserFn: parserFnT): parserFnT {.closure.} =
+    ignore(delimiterParserFn) + parserFn + ignore(delimiterParserFn)
+
+proc anyBetween*(startParserFn: parserFnT, stopParserFn: parserFnT): parserFnT {.inline.} =
+  ## Creates parser function with that matches anything between `startParserFn` and `stopParserFn`.
+  ## Ignores the delimiters in the tokens.
+  ## Example:
+  ##   anyBetween(ch('('), ch(')')) => Matches (abc)
+  between(startParserFn, stopParserFn)(anyUntil(stopParserFn))
+
+let anyBetweenPair* = proc(parserFn: parserFnT): parserFnT {.closure.} =
+  ## Creates parser function with that matches anything between matching `parserFns`
+  ## Ignores the delimiters in the tokens.
+  ## Example:
+  ##   anyBetweenPair(ch('"')) => Matches "abc"
+  anyBetween(parserFn, parserFn)
+
+# -- Parsing Aliases
+
+const newlineEolExpectedErr = "NewlineEol"
+let newlineOrEolParser = choice(@[
+  ch(NewLines),
+  endOfStream,
+])
+proc newlineOrEol*(parser: Parser): ParserResult =
+  newlineOrEolParser(parser)
+  .mapErr((x: ParserError) => x.setErrorExpectedField(newlineEolExpectedErr))
+
+const whitespaceEolExpectedErr = "WhitespaceEol"
+let whitespaceOrEolParser = choice(@[
+  ch(Whitespace),
+  newlineOrEolParser,
+])
+proc whitespaceOrEol*(parser: Parser): ParserResult =
+  whitespaceOrEolParser(parser)
+  .mapErr((x: ParserError) => x.setErrorExpectedField(whitespaceEolExpectedErr))
+
+# -- Tests
+
+when isMainModule:
+  let testParser123 = initParserResult("123")
+  let testAbc1Parser = initParserResult("abc1")
+
+  block testParsingFunctions:
+    let ch1 = ch('1')
+
+    # Success
+    assert testParser123.flatMap(ch1).tokensToString() == "1"
+    assert testParser123.flatMap(anyCh).tokensToString() == "1"
+    assert testParser123.flatMap(str("123")).tokensToString() == "123"
+
+    # Mismatch
+    assert testParser123.flatMap(ch('2')).error().kind == charMismatchErr
+    assert testParser123.flatMap(ch(Letters)).error().kind == charMismatchErr
+    assert testParser123.flatMap(str("1234")).error().kind == endOfStringErr
+    assert testParser123.flatMap(str("456")).error().kind == charMismatchErr
+
+    # Out of bounds
+    # assert initParserResult("").flatMap(ch1).error().kind == endOfStringErr
+    assert initParserResult("1").flatMap(ch1).flatMap(ch1).error().kind == endOfStringErr
+
+    # Stream end reached
+    assert initParserResult("1").flatMap(ch1).isStreamCompleted() == true
+    assert initParserResult("12").flatMap(ch1).isStreamCompleted() == false
+    assert initParserResult("").flatMap(ch1).isStreamCompleted() == false
+    assert testParser123.flatMap(str("123")).isStreamCompleted() == true
+
+    # endOfStream
+    assert testParser123.flatMap(str("123") + endOfStream).tokensToString() == "123"
+
+  block testParsingApi:
+    # plus, +
+    assert testAbc1Parser.flatMap(str("abc") + ch('1')).tokensToString() == "abc1"
+    assert testParser123.flatMap(str("12").plus(digit)).tokensToString() == "123"
+
+    # optional
+    assert testParser123.flatMap(optional(ch('1'))).tokensToString() == "1"
+    assert testParser123.flatMap(optional(ch('2'))).tokensToString() == ""
+
+    # ignore
+    assert testParser123.flatMap(ignore(ch('1'))).tokensToString() == ""
+
+    # peek
+    assert testParser123.flatMap(ch('1') + peekCurrent(ch('2')) + ch('2')).tokensToString() == "12"
+    assert testParser123.flatMap(ch('1') + peekCurrent(ch('1'))).isErr() == true
+    assert testParser123.flatMap(peekCurrent(startOfStream)).isOk() == true
+    assert testParser123.flatMap(ch('1') + peekBack1(startOfStream)).isOk() == true
+
+    # manyUntil
+    assert testAbc1Parser.flatMap(manyUntil(anyCh, digit)).tokensToString() == "abc"
+
+    # anyUntil
+    assert testAbc1Parser.flatMap(anyUntil(digit)).tokensToString() == "abc"
+
+    # choice
+    assert testAbc1Parser.flatMap(choice(@[digit, ch('a')])).tokensToString() == "a"
+    assert testAbc1Parser.flatMap(choice(@[digit])).error().kind == choiceMismatchErr
+
+    # parse
+    assert testAbc1Parser.flatMap(following(@[ch('a'), str("bc"), digit])).tokensToString() == "abc1"
+
+  block testParsingHelpers:
+    let testParenParser = initParserResult("(123)")
+    let testQuoteParser = initParserResult("\"123\"")
+    let testQuote = ch('"')
+    let testBetweenParen = between(ch('('), ch(')'))
+    let testBetweenQuotes = betweenPair(ch('"'))
+
+    # between
+    assert testParenParser.flatMap(testBetweenParen(str("123"))).tokensToString() == "123"
+    assert testQuoteParser.flatMap(testBetweenQuotes(str("123"))).tokensToString() == "123"
+
+    # anyBetween
+    assert testParenParser.flatMap(anyBetween(ch('('), ch(')'))).tokensToString() == "123"
+    assert testQuoteParser.flatMap(anyBetweenPair(testQuote)).tokensToString() == "123"
+
+  block testParsingAliases:
+    assert initParserResult("").flatMap(newlineOrEol).isOk() == true
+    assert initParserResult("abc ").flatMap(str("abc") + newlineOrEol).error().expected == newlineEolExpectedErr
+    assert initParserResult("").flatMap(whitespaceOrEol).isOk() == true
+    assert initParserResult("abc ").flatMap(str("abc") + whitespaceOrEol + whitespaceOrEol).tokensToString() == "abc "
+
+  block testImplementations:
+    let testSentenceStr = "This is a sentence\n\nFollowing another sentence."
+    let testSentenceParser = initParserResult(testSentenceStr)
+
+    let testSentence1 = following(@[anyUntil(newline), newline, newlineOrEol])
+    .plus(manyUntil(choice(@[letter, whitespace]), ch('.')) + ch('.') + newlineOrEol)
+
+    assert testSentenceParser.flatMap(testSentence1).tokensToString() == testSentenceStr

src_v2/parser/parser_types.nim

@@ -0,0 +1,353 @@
+import std/[
+  strutils,
+  strformat,
+  collections/sequtils,
+  sugar,
+]
+import fp/[
+  resultM,
+]
+import fusion/matching
+import ../utils/str
+
+{.experimental: "caseStmtMacros".}
+
+type
+  ParserState* = ref object
+    stream*: string
+    position*, lastPosition*: int
+
+  parserTokenCharValueT* = char
+  parserTokenStringValueT* = string
+  ParserTokenKind* = enum
+    parserTokenChar
+    parserTokenString
+  ParserToken* = ref object
+    case kind*: ParserTokenKind
+      of parserTokenChar:
+        charValue*: parserTokenCharValueT
+      of parserTokenString:
+        stringValue*: parserTokenStringValueT
+
+  Parser* = ref object
+    state*: ParserState
+    tokens*: seq[ParserToken]
+  ParserErrorKind* = enum
+    choiceMismatchErr
+    charMismatchErr
+    endOfStringErr
+    startOfStringErr
+  ParserError* = ref object
+    kind*: ParserErrorKind
+    unexpected*: string
+    expected*: string
+    index*: int
+    parser*: Parser
+  ParserResult* = Result[Parser, ParserError]
+
+type parserFnT* = proc(t0: Parser): ParserResult
+
+# -- Initalizers
+
+func initParserToken*(x: char): ParserToken =
+  ## Initialize `ParserToken` as `parserTokenChar` with value `x`.
+  ParserToken(kind: parserTokenChar, charValue: x)
+func initParserToken*(x: string): ParserToken =
+  ## Initialize `ParserToken` as `parserTokenString` with value `x`.
+  ParserToken(kind: parserTokenString, stringValue: x)
+
+func initParser*(
+  stream: string,
+  tokens = newSeq[ParserToken](),
+  position = -1,
+  lastPosition = 0,
+): Parser =
+  ## Initialize `Parser` with `stream`.
+  Parser(
+    state: ParserState(
+      stream: stream,
+      position: position,
+      lastPosition: lastPosition,
+    ),
+    tokens: tokens,
+  )
+
+func initParserResult*(
+  stream: string,
+  tokens = newSeq[ParserToken](),
+  position = -1,
+  lastPosition = 0,
+): ParserResult =
+  ## Initialize `ParserResult.ok` with `stream`.
+  ParserResult.ok(initParser(
+    stream,
+    tokens,
+    position,
+    lastPosition,
+  ))
+
+# -- Equalizers
+
+func `==`*(a: ParserToken, b: ParserToken): bool =
+  ## Compare two `ParserToken` objects.
+  case ((a.kind, b.kind)):
+    of (parserTokenChar, parserTokenChar): a.charValue == b.charValue
+    of (parserTokenString, parserTokenString): a.stringValue == b.stringValue
+    else: false
+
+# -- Getters
+
+func toString*(x: ParserToken): string =
+  ## Get the `ParserToken` value `x` as a string.
+  case x.kind:
+    of parserTokenChar:
+      $x.charValue
+    of parserTokenString:
+      x.stringValue
+
+func toString*(tokens: seq[ParserToken]): string =
+  ## Get the seq `ParserToken` value `x` as a string.
+  tokens.foldl(a & b.toString(), "")
+
+# -- Modifiers
+
+func flattenTokens*(parser: Parser): Parser =
+  ## Flatten tokens in `parser` as a string `ParserToken`.
+  let token = parser.tokens
+  .foldl(a & b.toString(), "")
+  .initParserToken()
+
+  Parser(
+    state: parser.state,
+    tokens: @[token]
+  )
+
+func flattenTokensResult*(parser: Parser): ParserResult =
+  parser
+  .flattenTokens()
+  .ok()
+
+func emptyTokens*(parser: Parser): Parser =
+  ## Empty `parser` tokens.
+  Parser(
+    state: parser.state,
+    tokens: newSeq[ParserToken](),
+  )
+
+func foldTokens*[T](
+  parserResult: ParserResult,
+  onErrorFn: ParserError -> T,
+  onSuccessFn: seq[ParserToken] -> T,
+): T =
+  ## Fold over `tokens` inside `ParserResult` with `onSuccessFn` or `onErrorFn`.
+  if parserResult.isOk():
+    onSuccessFn(parserResult.unsafeGet().tokens)
+  else:
+    let err = parserResult.error()
+    onErrorFn(err)
+
+func tokensToString*(parserResult: ParserResult, fallback = ""): string =
+  parserResult.foldTokens(
+    err => fallback,
+    xs => xs.toString(),
+  )
+
+func tokensToString*(tokens: seq[ParserToken]): string =
+  tokens.foldl(a & b.toString(), "")
+
+func setErrorExpectedField*(err: ParserError, expected: string): ParserError =
+  ParserError(
+    kind: err.kind,
+    unexpected: err.unexpected,
+    expected: expected,
+    index: err.index,
+    parser: err.parser,
+  )
+
+# -- Stringifiers
+
+func pprint*(x: ParserToken): string =
+  let str = toString(x)
+  let escapedChar = if str == "\n": "\\n"
+                    else: str
+  &"""ParserToken("{escapedChar}")
+"""
+
+func `$`*(x: ParserToken): string = pprint(x)
+
+const LEFT_HIGHLIGHT_CHAR = ">>"
+const RIGHT_HIGHLIGHT_CHAR = "<<"
+func highlightStreamPosition(stream: string, position: int): string =
+  if position < 0: return stream
+  if position > stream.len - 1: return stream
+
+  let aIndex = position - 1
+  let a = if aIndex < 0: ""
+          else: stream[0..aIndex]
+
+  let ch = stream[position]
+
+  let bIndex = position + 1
+  let b = if bIndex > stream.len - 1: ""
+          else: stream[bIndex..stream.len - 1]
+
+  return a & LEFT_HIGHLIGHT_CHAR & ch & RIGHT_HIGHLIGHT_CHAR & b
+
+func highlightStreamPosition2(stream: string, position: int): string =
+  if position < 0: return stream
+  if position > stream.len - 1: return stream
+
+  let ch = stream[position]
+
+  let (lineStartPosition, lineEndPosition) =
+    case ch:
+      of '\n':
+        let lineStartPosition = (position - 1).max(0)
+        let lineEndPosition = (position + 1).min(stream.len - 1)
+        (lineStartPosition, lineEndPosition)
+      else:
+        (position, position)
+
+  let startIndex = stream.rfind("\n", 0, lineStartPosition)
+  let lineStartIndex =
+    case startIndex:
+      of -1: 0
+      else: startIndex + 1
+
+  let endIndex = stream.find("\n", lineEndPosition)
+  let lineEndIndex =
+    case endIndex:
+      of -1: stream.len
+      else: endIndex
+
+  let spaceChars = " ".repeat((position - lineStartIndex).max(0))
+  let lineChars = "_".repeat((lineEndIndex - position).max(0) + 10)
+
+  let escapedChar =
+    case ch:
+      of '\n': "\\n"
+      of ' ': "\\s"
+      else: $ch
+
+  let insertMessageAtIndex =
+    case ch:
+      # Print indicator for newlines on the previous line, which looks better for the reader
+      of '\n': (lineEndIndex - 1).max(1)
+      else: lineEndIndex
+
+  let beforeNewline =
+    case (startIndex, ch):
+      # Always print newline for newline at the stream begin
+      of (-1, '\n'): "\n"
+      # Don't insert a newline when the character is a newline between newlines
+      of (_, '\n'): ""
+      else: "\n"
+
+  # debugEcho "char: " & $ch
+  # debugEcho "position: " & $position
+  # debugEcho "startIndex: " & $lineStartIndex
+  # debugEcho "endIndex: " & $lineEndIndex
+  # debugEcho "insertMessageAtIndex: " & $insertMessageAtIndex
+
+  stream.dup(insert(&"{beforeNewline}{spaceChars}^{lineChars} Char at \"{escapedChar}\"\n", insertMessageAtIndex))
+
+func `$`*(x: ParserState): string =
+  &"""ParserState(
+  stream: "{x.stream.highlightStreamPosition(x.position)}",
+  position: {x.position},
+  lastPosition: {x.lastPosition},
+)"""
+
+func `$`*(x: Parser): string =
+  &"""Parser(
+  state: {indentAfterNewline($x.state, 2)},
+  tokens: {indentAfterNewline($x.tokens, 2)},
+)"""
+
+func `$`*(x: ParserError): string =
+  case x:
+    of charMismatchErr(expected: @expected, parser: @parser, index: @index, unexpected: @unexpected):
+      # TODO: Only works for single line right now
+      let original = parser.state.stream
+      .deleteAfterNewline(parser.state.position)
+      let errSpace = " ".repeat(max(0, index))
+
+      &"""Parsing Error (Character Mismatch Error):
+{original}
+{errSpace}^ Expected '{expected}' but got '{unexpected}'"""
+    of choiceMismatchErr(expected: @expected, parser: @parser, index: @index, unexpected: @unexpected):
+      let original = parser.state.stream
+      .deleteAfterNewline(parser.state.position)
+      let errSpace = " ".repeat(max(0, index))
+
+      &"""Parsing Error (Character Mismatch Error):
+{original}
+{errSpace}^ Expected '{expected}' but got '{unexpected}'"""
+
+    of endOfStringErr(parser: @parser, index: @index):
+      let original = parser.state.stream
+      .deleteAfterNewline(parser.state.position)
+      let errSpace = " ".repeat(max(0, index))
+
+      &"""Parsing Error (EndOfString Expected):
+{original}
+{errSpace}^ Expected 'EndOfString' at {index} but got {original.len - 1}"""
+
+    of startOfStringErr(parser: @parser, index: @index):
+      let original = parser.state.stream
+      .deleteAfterNewline(parser.state.position)
+      let errSpace = " ".repeat(max(0, index))
+
+      &"""Parsing Error (StartOFString Expected):
+{original}
+{errSpace}^ Expected 'StartOfString' at index {index}"""
+
+    else: "ParseError"
+
+when isMainModule:
+  block testEqualizers:
+    assert initParserToken("a") == initParserToken("a")
+    assert initParserToken('a') == initParserToken('a')
+    assert initParserToken("a") != initParserToken('a')
+
+  block testGetters:
+    # toString
+    assert initParserToken("a").toString() == "a"
+    assert initParserToken('a').toString() == "a"
+
+  block testModifiers:
+    let testTokensSeq = @[initParserToken("a"), initParserToken('b'), initParserToken("c")]
+    let testExpectedStr = "abc"
+    let testTokensSeqParser = initParser(
+      stream = testExpectedStr,
+      tokens = testTokensSeq,
+      position = testTokensSeq.len - 1,
+    )
+    let testTokensSeqParserResult = ParserResult.ok(testTokensSeqParser)
+    let testTokensSeqParserResultErr = ParserResult.err(ParserError(
+      kind: charMismatchErr,
+      unexpected: "a",
+      expected: "b",
+      index: 0,
+      parser: testTokensSeqParser,
+    ))
+
+    # flattenTokens
+    assert testTokensSeqParser.flattenTokens().tokens[0] == initParserToken("abc")
+
+    # emptyTokens
+    assert testTokensSeqParser.emptyTokens().tokens.len == 0
+
+    # foldTokens
+    assert testTokensSeqParserResult.foldTokens(
+      err => "Failure",
+      xs => xs.toString(),
+    ) == testExpectedStr
+    assert testTokensSeqParserResultErr.foldTokens(
+      err => "Failure",
+      xs => xs.toString(),
+    ) == "Failure"
+
+    # tokensToString
+    assert testTokensSeqParserResult.tokensToString() == testExpectedStr
+    assert testTokensSeq.tokensToString() == testExpectedStr

src_v2/utils/fp.nim

@@ -0,0 +1,37 @@
+import std/sugar
+import fp/maybe
+import results
+
+func last*[T](xs: seq[T]): Maybe[T] =
+  if xs.len == 0:
+     nothing(T)
+  else:
+    just(xs[^1])
+
+template isSome*(self: Result): bool = self.isOk()
+template isNone*(self: Result): bool = self.isErr()
+
+proc findMaybe*[T](xs: seq[T], fn: T -> bool): Maybe[T] =
+  for x in xs:
+    if fn(x):
+      return Just(x)
+  return Nothing[T]()
+
+proc findMaybeFn*[T, B](fns: seq[T {.nimcall.} -> Maybe[B]], val: T): Maybe[B] =
+  for fn in fns:
+    let res = fn(val)
+    if res.isDefined():
+      return res
+  return Nothing[B]()
+
+proc notNegative*[int](x: Maybe[int]): Maybe[int] =
+  ## Maps nil object to nothing
+  x.filter(i => i >= 0)
+
+when isMainModule:
+  echo @[
+  (x: int) => (if x == 2: Just("foo") else: Nothing[string]()),
+  ].findMaybeFn(2)
+
+  assert last(@[1,2,3]) == just(3)
+  assert last[int](@[]) == nothing(int)

src_v2/utils/parsec_test.nim

@@ -0,0 +1,15 @@
+import sequtils
+import std/sugar
+import microparsec
+import results
+
+echo toSeq(1..1000000)
+
+# let headlineParser = manyTill(ch '*', space)
+# .flatMap((stars: seq[char]) => pure(stars))
+# # .flatMap((stars) => manyTill(anyChar, endOfLine)
+# #     .flatMap(headline => pure(stars, headline))
+# # )
+
+# echo headlineParser.parse("*** Headline")
+# echo headlineParser.parse("* Headline")

src_v2/utils/parser.nim

@@ -0,0 +1,28 @@
+import std/parseutils
+
+proc fastSubstr(s: string; token: var string; start, length: int) =
+  token.setLen length
+  for i in 0 ..< length: token[i] = s[i+start]
+
+proc parseUntilBackwards*(s: string, token: var string, until: string,
+                 start = 0): int {.inline.} =
+  ## Parses a token and stores it in ``token``. Returns
+  ## the number of the parsed characters or 0 in case of an error. A token
+  ## consists of any character that comes before the `until`  token.
+  runnableExamples:
+    var myToken: string
+    doAssert parseUntil("Hello World", myToken, "Wor") == 6
+    doAssert myToken == "Hello "
+    doAssert parseUntil("Hello World", myToken, "Wor", 2) == 4
+    doAssert myToken == "llo "
+  var i = s.len
+  while i > 0:
+    if until.len > 0 and s[i] == until[until.len - 1]:
+      var u = 1
+      while i+u < s.len and u < until.len and s[i+u] == until[u]:
+        inc u
+      if u >= until.len: break
+    dec(i)
+  result = i-start
+  fastSubstr(s, token, start, result)
+  #token = substr(s, start, i-1)

src_v2/utils/printers.nim

@@ -0,0 +1,44 @@
+import std/[
+  options,
+  sequtils,
+  strformat,
+  strutils,
+  sugar,
+]
+
+const INDENT_SIZE* = 2;
+
+func stringifyFields*(
+  xs: seq[tuple[
+    field: string,
+    value: string,
+    print: bool
+  ]],
+  indent = 0,
+): string =
+  xs
+  .filter(x => x.print)
+  .map(x => x.field & ": " & $x.value)
+  .join(",\n")
+
+func stringifyBlock*(blockName: string, indent = 0, xs: varargs[string]): string =
+  let fieldIndent = indent + INDENT_SIZE
+
+  concat(
+    @[&"{blockName}("],
+    @xs.mapIt(it.indent(fieldIndent)),
+    @[")"],
+  )
+  .join("\n")
+
+func stringifySeq*[T](xs: seq[T], stringifyFn: (T) -> string, indent = 0): string =
+  let fieldIndent = indent + INDENT_SIZE
+  @[
+    "@[",
+    xs
+    .mapIt(it.stringifyFn())
+    .join(",\n")
+    .indent(fieldIndent),
+    "]",
+  ]
+  .join("\n")

src_v2/utils/str.nim

@@ -0,0 +1,60 @@
+import std/[
+  strutils,
+  math,
+]
+import fusion/matching
+
+{.experimental: "caseStmtMacros".}
+
+func prettyExpectedSet*(x: set[char]): string =
+  ## Pretty print value for a set `x` of characters
+  case x:
+    of AllChars:
+      "AllChars {'\x00'..'\xFF'}"
+    of Digits:
+      "Digits {'0'..'9'}"
+    of HexDigits:
+      "HexDigits {'0'..'9', 'A'..'F', 'a'..'f'}"
+    of Letters:
+      "Letters {'A'..'Z', 'a'..'z'}"
+    of Newlines:
+      "Newlines {'\r', '\n'}"
+    of Whitespace:
+      "Whitespace {' ', '\t', '\v', '\r', '\n', '\f'}"
+    else:
+      $x
+
+func indentAfterNewline*(str: string, count: int): string =
+  ## Indent lines following the first line of `str` by `count`.
+  ## Useful for indenting nested keys of stringify functions.
+  var strDup = str.indent(count)
+  strDup.delete(0..count - 1)
+  strDup
+
+proc safeDelete*(str: string, slice: Slice[int]): string =
+  ## Deletes the items `str[slice]`, ignoring elements out of range.
+  if slice.a > str.len - 1:
+    str
+  else:
+    let fromIndex = clamp(slice.a, 0..str.len)
+    let toIndex = clamp(slice.b, 0..str.len - 1)
+
+    var strDup = str
+    strDup.delete(fromIndex..toIndex)
+    strDup
+
+func findAndDelete*(str: string, chars: set[char], start = 0, last = str.len - 1): string =
+  ## Find the next instance of `chars` from `start`.
+  ## When found delete characters until `last`.
+  # Prevent passing negative numbers (e.g.: initial parser)
+  if start >= 0 and last >= 0:
+    let startChar = str.find(chars, start, last)
+    if startChar == -1:
+      str
+    else:
+      str.safeDelete(startChar..last)
+  else: str
+
+func deleteAfterNewline*(str: string, start = 0): string =
+  ## Delete string after next Newline from `start`.
+  findAndDelete(str, Newlines, start)