Merge pull request #2849 from ozra/feature-2811-hump-snake-dash

Feature #2811 hump, snake and now dash

compiler/idents.nim

@@ -12,7 +12,7 @@
 # id. This module is essential for the compiler's performance.
 
 import 
-  hashes, strutils
+  hashes, strutils, etcpriv
 
 type 
   TIdObj* = object of RootObj
@@ -37,6 +37,8 @@ proc cmpIgnoreStyle(a, b: cstring, blen: int): int =
   while j < blen:
     while a[i] == '_': inc(i)
     while b[j] == '_': inc(j)
+    while isMagicIdentSeparatorRune(a, i): inc(i, magicIdentSeparatorRuneByteWidth)
+    while isMagicIdentSeparatorRune(b, j): inc(j, magicIdentSeparatorRuneByteWidth)
     # tolower inlined:
     var aa = a[i]
     var bb = b[j]

compiler/lexer.nim

@@ -17,7 +17,7 @@
 
 import
   hashes, options, msgs, strutils, platform, idents, nimlexbase, llstream,
-  wordrecg
+  wordrecg, etcpriv
 
 const
   MaxLineLength* = 80         # lines longer than this lead to a warning
@@ -140,10 +140,12 @@ proc isKeyword*(kind: TTokType): bool =
 proc isNimIdentifier*(s: string): bool =
   if s[0] in SymStartChars:
     var i = 1
-    while i < s.len:
+    var sLen = s.len
+    while i < sLen:
       if s[i] == '_':
         inc(i)
-        if s[i] notin SymChars: return
+      elif isMagicIdentSeparatorRune(cstring s, i):
+        inc(i, magicIdentSeparatorRuneByteWidth)
       if s[i] notin SymChars: return
       inc(i)
     result = true
@@ -632,16 +634,27 @@ proc getSymbol(L: var TLexer, tok: var TToken) =
     var c = buf[pos]
     case c
     of 'a'..'z', '0'..'9', '\x80'..'\xFF':
-      h = h !& ord(c)
+      if  c == '\226' and
+          buf[pos+1] == '\128' and
+          buf[pos+2] == '\147':  # It's a 'magic separator' en-dash Unicode
+        if buf[pos + magicIdentSeparatorRuneByteWidth] notin SymChars:
+          lexMessage(L, errInvalidToken, "–")
+          break
+        inc(pos, magicIdentSeparatorRuneByteWidth)
+      else:
+        h = h !& ord(c)
+        inc(pos)
     of 'A'..'Z':
       c = chr(ord(c) + (ord('a') - ord('A'))) # toLower()
       h = h !& ord(c)
+      inc(pos)
     of '_':
       if buf[pos+1] notin SymChars:
         lexMessage(L, errInvalidToken, "_")
         break
+      inc(pos)
+
     else: break
-    inc(pos)
   h = !$h
   tok.ident = getIdent(addr(L.buf[L.bufpos]), pos - L.bufpos, h)
   L.bufpos = pos