core: add match-str and matches? to regex

core/String.carp

@@ -100,8 +100,10 @@
 
   (register find (Fn [&String &String] Int))
   (register match (Fn [&String &String] (Array String)))
+  (register match-str (Fn [&String &String] String))
   (register global-match (Fn [&String &String] (Array (Array String))))
   (register substitute (Fn [&String &String &String Int] String))
+  (defn matches? [s pat] (/= (find s pat) -1))
 )
 
 (defmodule StringCopy

core/carp_regex.h

@@ -445,6 +445,34 @@ Array String_match(string* s, string* p) {
   return a;
 }
 
+string String_match_MINUS_str(string* s, string* p) {
+  string str = *s;
+  string pat = *p;
+  int lstr = strlen(str);
+  int lpat = strlen(pat);
+  MatchState ms;
+  string s1 = str;
+  int anchor = (*pat == '^');
+  if (anchor) {
+    pat++; lpat--;  /* skip anchor character */
+  }
+  prepstate(&ms, str, lstr, pat, lpat);
+  do {
+    string res;
+    reprepstate(&ms);
+    if ((res=match(&ms, s1, pat))) {
+      int start = (s1 - str) + 1;
+      int end = res - str + 1;
+      int len = end - start;
+      res = malloc(len + 1);
+      memcpy(res, str, len);
+      res[len] = '\0';
+      return res;
+    }
+  } while (s1++ < ms.src_end && !anchor);
+  return String_empty();
+}
+
 /* state for 'gmatch' */
 typedef struct GMatchState {
   string src;  /* current position */

test/string.carp

@@ -110,11 +110,31 @@
                   &(match "   " "(\\d)")
                   "match works as expected if not found"
     )
+    (assert-equal test
+                  true
+                  (matches? "banana" "ana")
+                  "matches? works as exptected"
+    )
+    (assert-equal test
+                  true
+                  (matches? "banana" "ano")
+                  "matches? works as exptected II"
+    )
     (assert-equal test
                   &[@"3" @"4"]
                   (Array.nth &(global-match "1-2 2-3 3-4 4-5" "(\\d)-(\\d)") 2)
                   "global-match works as expected"
     )
+    (assert-equal test
+                  "1-2"
+                  &(match-str "1-2 2-3 3-4 4-5" "(\\d)-(\\d)")
+                  "match-str works as expected"
+    )
+    (assert-equal test
+                  ""
+                  &(match-str "1-2 2-3 3-4 4-5" "erik")
+                  "match-str works as expected II"
+    )
     (assert-equal test
                   "sub 2-3 3-4"
                   &(substitute "1-2 2-3 3-4" "(\\d)-(\\d)" "sub" 1)