Implement {Match,Cursor}.at-{key,pos}

sorear · Sep 13, 2010 · bedd19a · bedd19a
1 parent ba15f79
commit bedd19a
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diff --git a/lib/Cursor.cs b/lib/Cursor.cs
@@ -313,6 +313,42 @@ public Cursor(IP6 proto, string text)
         return new Cursor(klass, xact, backing, backing_ca, npos);
     }
 
+    // TODO: keep variables around so { $<foo> = 1 } will work
+    public Variable GetKey(string str) {
+        PSN<string[]> cn_it = capnames;
+        PSN<Cursor> cr_it = captures;
+        VarDeque caps = new VarDeque();
+        bool list = false;
+
+        while (cr_it != null) {
+            foreach (string cn in cn_it.obj) {
+                if (cn == str)
+                    goto yes;
+            }
+            goto no;
+yes:
+            if (cr_it.obj == null) {
+                list = true;
+            } else {
+                caps.Unshift(Kernel.NewRWScalar(cr_it.obj));
+            }
+no:
+            cr_it = cr_it.next;
+            cn_it = cn_it.next;
+        }
+
+        if (list) {
+            DynObject l = new DynObject(RxFrame.ListMO);
+            l.SetSlot("flat", Kernel.NewROScalar(Kernel.AnyP));
+            l.SetSlot("items", caps);
+            l.SetSlot("rest", new VarDeque());
+            return Kernel.NewRWListVar(l);
+        } else {
+            return caps.Count() != 0 ? caps[0] :
+                Kernel.NewRWScalar(Kernel.AnyP);
+        }
+    }
+
     public Variable SimpleWS() {
         int l = backing_ca.Length;
         int p = pos;

diff --git a/src/CodeGen.pm b/src/CodeGen.pm
@@ -90,6 +90,7 @@ use 5.010;
             { At           => [m => 'Cursor'],
               pos          => [f => 'Int32'],
               from         => [f => 'Int32'],
+              GetKey       => [m => 'Variable'],
               backing      => [f => 'String'],
               SimpleWS     => [m => 'Variable'] },
         'Lexer' =>

diff --git a/test2.pl b/test2.pl
@@ -18,4 +18,31 @@
     }
 }
 
+use MONKEY_TYPING;
+augment class Match {
+    method at-key($k) { Q:CgOp {
+        (rawcall (cast Cursor (@ {self})) GetKey (unbox String (@ {$k.Str})))
+    } }
+    method at-pos($i) { self.at-key($i) }
+}
+augment class Cursor {
+    method at-key($k) { Q:CgOp {
+        (rawcall (cast Cursor (@ {self})) GetKey (unbox String (@ {$k.Str})))
+    } }
+    method at-pos($i) { self.at-key($i) }
+}
+
+{
+    my $ma = (grammar {
+        regex TOP { <foo> <bar> }
+        regex foo { \d+ }
+        regex bar { \w+ }
+    }).parse("123abc");
+    ok $ma<foo> ~~ Match, "<foo> sub is a Match";
+    is $ma<foo>, "123", "<foo> sub got 123";
+    ok $ma<bar> ~~ Match, "<bar> sub is a Match";
+    is $ma<bar>, "abc", "<bar> sub got 123";
+    ok !$ma<quux>, "no <quux> sub";
+}
+
 done-testing;