Implement first cut of s/// syntax. Uses .subst under the hood, so it…

…'s as capable/incapable as .subst.

build/Makefile.in

@@ -195,6 +195,7 @@ CORE_SOURCES = \
   src/core/Regex.pm \
   src/core/Junction.pm \
   src/core/Grammar.pm \
+  src/core/Substitution.pm \
   src/core/system.pm \
   src/cheats/match-bool.pm \
   src/cheats/setup-io.pm \

src/Perl6/Actions.pm

@@ -2132,6 +2132,30 @@ method quote:sym<m>($/) {
     make create_code_object($past, 'Regex', 0, '');
 }
 
+method quote:sym<s>($/) {
+    # Build the regex.
+    my $regex_ast := Regex::P6Regex::Actions::buildsub($<p6regex>.ast);
+    my $regex := create_code_object($regex_ast, 'Regex', 0, '');
+
+    # Quote needs to be closure-i-fied.
+    my $closure_ast := PAST::Block.new(
+        PAST::Stmts.new(),
+        PAST::Stmts.new(
+            $<quote_EXPR>.ast
+        )
+    );
+    my $closure := create_code_object($closure_ast, 'Block', 0, '');
+
+    # Make a Substitution.
+    $regex.named('matcher');
+    $closure.named('replacer');
+    make PAST::Op.new(
+        :pasttype('callmethod'), :name('new'),
+        PAST::Var.new( :name('Substitution'), :scope('package') ),
+        $regex, $closure
+    );
+}
+
 method quote_escape:sym<$>($/) {
     #make $<variable>.ast;
     # my $a = 3; say "$a".WHAT # Gives Int, not Str with the above. Force

src/Perl6/Grammar.pm

@@ -989,7 +989,13 @@ token quote:sym<m> {
     | '{'<p6regex=.LANG('Regex','nibbler')>'}'
     ]
 }
-
+token quote:sym<s> {
+    <sym> >> 
+    '/'
+    <p6regex=.LANG('Regex','nibbler')>
+    <?[/]>
+    <quote_EXPR: ':qq'>
+}
 
 token quote_escape:sym<$>   { <?[$]> <?quotemod_check('s')> <variable> }
 token quote_escape:sym<{ }> { <?[{]> <?quotemod_check('c')> <block> }

src/core/Substitution.pm

@@ -0,0 +1,8 @@
+class Substitution {
+    has $!matcher;
+    has $!replacer;
+
+    method ACCEPTS($topic is rw) {
+        $topic = $topic.subst($!matcher, $!replacer);
+    }
+}

src/core/operators.pm

@@ -11,6 +11,12 @@ our multi infix:<~~>(Mu $topic, Regex $matcher) {
     };
 }
 
+class Substitution { ... }
+our multi infix:<~~>(Mu $topic is rw, Substitution $matcher) {
+    $matcher.ACCEPTS($topic)
+}
+
+
 our multi infix:<!~~>(Mu $topic, Mu $matcher) {
     $matcher.REJECTS($topic)
 }