Started refactor

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)