Better chars

runtime/Std.i

@@ -5,6 +5,9 @@ F,tl;
 F,readLine;
 F,stringcat;
 F,matchSubString;
+F,substring;
+F,regexp;
+F,regexpMatch;
 F,sprintf;
 F,makeString;
 F,printf;

runtime/runtime.c

@@ -8,6 +8,7 @@
 # include <sys/mman.h>
 # include <assert.h>
 # include <errno.h>
+# include <regex.h>
 
 # define __ENABLE_GC__
 # ifndef __ENABLE_GC__
@@ -295,6 +296,44 @@ extern int LmatchSubString (char *subj, char *patt, int pos) {
   return BOX(strncmp (subj + UNBOX(pos), patt, n) == 0);
 }
 
+extern void* Lsubstring (void *subj, int p, int l) {
+  data *d = TO_DATA(subj);
+  int pp = UNBOX (p), ll = UNBOX (l);
+  
+  if (pp + ll <= LEN(d->tag)) {
+    data *r;
+    
+    __pre_gc ();
+  
+    r = (data*) alloc (ll + 1 + sizeof (int));
+
+    r->tag = STRING_TAG | (ll << 3);
+
+    strncpy (r->contents, (char*) subj + pp, ll);
+    
+    __post_gc ();
+
+    return r->contents;    
+  }
+  
+  failure ("substring: index out of bounds (position=%d, length=%d, subject length=%d)", pp, ll, LEN(d->tag));
+}
+
+extern struct re_pattern_buffer *Lregexp (char *regexp) {
+  struct re_pattern_buffer *b = (struct re_pattern_buffer*) malloc (sizeof (struct re_pattern_buffer));
+  int n = re_compile_pattern (regexp, strlen (regexp), b);
+
+  if (n != 0) {
+    failure ("%", strerror (n));
+  };
+
+  return b;
+}
+
+extern int LregexpMatch (struct re_pattern_buffer *b, char *s, int pos) {
+  return BOX (re_match (b, s, LEN(TO_DATA(s)->tag), UNBOX(pos), 0));
+}
+
 extern int Lcompare (void *p, void *q) {
 # define COMPARE_AND_RETURN(x,y) do if (x != y) return BOX(x - y); while (0)
   if (UNBOXED(p)) {
@@ -630,7 +669,7 @@ extern void Bmatch_failure (void *v, char *fname, int line, int col) {
   failure ("match failure at %s:%d:%d, value '%s'\n", fname, line, col, stringBuf.contents);
 }
 
-extern void* /*Lstrcat*/ i__Infix_4343 (void *a, void *b) {
+extern void* /*Lstrcat*/ Li__Infix_4343 (void *a, void *b) {
   data *da = (data*) BOX (NULL);
   data *db = (data*) BOX (NULL);
   data *d  = (data*) BOX (NULL);
@@ -642,10 +681,12 @@ extern void* /*Lstrcat*/ i__Infix_4343 (void *a, void *b) {
   
   d  = (data *) alloc (sizeof(int) + LEN(da->tag) + LEN(db->tag) + 1);
 
-  d->tag = LEN(da->tag) + LEN(db->tag);
+  d->tag = STRING_TAG | ((LEN(da->tag) + LEN(db->tag)) << 3);
 
-  strcpy (d->contents, da->contents);
+  strncpy (d->contents               , da->contents, LEN(da->tag));
-  strcat (d->contents, db->contents);
+  strncpy (d->contents + LEN(da->tag), db->contents, LEN(db->tag));
+  
+  d->contents[LEN(da->tag) + LEN(db->tag)] = 0;
 
   __post_gc();
   

src/X86.ml

@@ -589,8 +589,12 @@ class env prg =
         let rec iterate i =
           if i < n
           then (
-            if x.[i] = '"' then Buffer.add_string buf "\\\""
+            (match x.[i] with
-            else Buffer.add_char buf x.[i];
+            | '"'  -> Buffer.add_string buf "\\\""
+            | '\n' -> Buffer.add_string buf "\n"
+            | '\t' -> Buffer.add_string buf "\t"
+            | c    -> Buffer.add_char buf c
+            );
             iterate (i+1)
           )
         in

stdlib/Matcher.expr

@@ -1,27 +1,59 @@
--- Matcher library for Ostap
+-- (C) Dmitry Boulytchev, St. Petersburg State University, JetBrains Research, 2020
+-- Matcher: simple string matching library.
 
-fun matcherCreate (pos, buf, line, col) {
+
+-- Create a regular expression representation.
+-- Arguments:
+--    r    --- a string representation for regular expression (as per GNU regexp)
+--    name --- a string describing the meaning of the expression in free form
+--             (e.g. "identifier", "string constant", etc.), used for error
+--             reporting
+fun createRegexp (r, name) {
+  return [regexp (r), name]
+}
+
+-- Create an immutable matcher.
+-- Arguments:
+--    buf --- a string to match in
+--    pos --- an integer beginning position to match from
+--    line, col --- line and column numbers
+-- This function is internal, do not use it directly.
+-- To initially create a matcher use initMatcher function (see below).
+fun matcherCreate (buf, pos, line, col) {
+  -- Shows a matcher in a readable form
   fun show () {
     return sprintf ("buf : %-40s\npos : %d\nline: %d\ncol : %d\n", buf, pos, line, col)
   }
-  
+
+  -- Calculates the number of remaining unmatched characters in the buffer
   fun rest () {
     return buf.length - pos
   }
-  
+
+  -- Moves the position pointer on given number of characters within one line (i.e. 
   fun shift (n) {
-    return matcherCreate (pos + n, buf, line, col + n)
+    return matcherCreate (buf, pos + n, line, col + n)
   }
-  
+
   fun matchString (s) {
     return
       if s.length > rest ()
-      then None
+      then Fail (sprintf ("""%s"" expected at %d:%d", s, line, col))
-      elif matchSubString (buf, s, pos) then Some (shift (s.length)) 
+      elif matchSubString (buf, s, pos) then Succ (shift (s.length), s) 
-      else None
+      else Fail (sprintf ("""%s"" expected at %d:%d", s, line, col))
       fi
   }
 
+  fun matchRegexp (r) {
+    local n;
+    
+    return
+      if (n := regexpMatch (r[0], buf, pos)) > 0
+      then Succ (shift (n), substring (buf, pos, n))
+      else Fail (sprintf ("%s expected at %d:%d", r[1], line, col))
+      fi
+  }
+  
   fun eof () {
     return rest () == 0
   }
@@ -29,32 +61,39 @@ fun matcherCreate (pos, buf, line, col) {
   return [
      show,
      eof,
-     matchString
+     matchString,
+     matchRegexp
   ]
 }
 
 fun show (m) {
-  return m [0]
+  return m [0] ()
 }
 
 fun eof (m) {
-  return m [1]
+  return m [1] ()
 }
 
 fun matchString (m, s) {
   return m [2] (s)
 }
 
-fun matcherInit (buf) {
+fun matchRegexp (m, r) {
-  return matcherCreate (0, buf, 1, 1)
+  return m [3] (r)
 }
 
+fun matcherInit (buf) {
+  return matcherCreate (buf, 0, 1, 1)
+}
+
+--fun parse (a) {
+ 
+--}
+
 local m = matcherInit ("abc");
 
-printf ("%s", m.show ());
+local ident = createRegexp ("[a-z][a-zA-Z_]*", "identifier");
-printf ("eof: %s\n", m.eof ().string);
+local ws    = createRegexp ("[ \n\t]+", "whitespace");
-printf ("matchString(""u""): %s\n", case m.matchString ("u") of Some (m) -> m.show () | _ -> "None" esac);
+local str   = createRegexp ("""\([^""]\|""""\)*""", "string literal");
-printf ("matchString(""a""): %s\n", case m.matchString ("a") of Some (m) -> m.show () | _ -> "None" esac);
+
-printf ("matchString(""ab""): %s\n", case m.matchString ("ab") of Some (m) -> m.show () | _ -> "None" esac);
+printf ("ident: %s\n", case m.matchRegexp (ident) of Succ (m, s) -> "(" ++ m.show  ++ ", " ++ s ++ ")" | Fail (err) -> err.string esac)
-printf ("matchString(""abc""): %s\n", case m.matchString ("abc") of Some (m) -> m.show () | _ -> "None" esac);
-printf ("matchString(""abcd""): %s\n", case m.matchString ("abcd") of Some (m) -> m.show () | _ -> "None" esac)