Add list associativity.

src/HLL/Actions.pm

@@ -4,17 +4,18 @@ method EXPR($/, $key?) {
     unless $key { return 0; }
     my $past := $<OPER>.peek_ast;
     unless $past { 
+        if $key eq 'LIST' { $key := 'infix'; }
         my $name := Q:PIR {
             $P0 = find_lex '$key'
             $S0 = $P0
             $S0 = downcase $S0
             %r = box $S0
-        } ~ ':<' ~ $key ~ '>';
-        $past := PAST::OP.new( :name($name), :node($/) ); 
+        } ~ ':<' ~ $<OPER><sym> ~ '>';
+        $past := PAST::Op.new( :name($name), :node($/) ); 
     }
-    $past[0] := $/[0].ast;
-    if $key eq 'INFIX' {
-       $past[1] := $/[1].ast;
+    if $key eq 'POSTFIX' { $past.unshift($/[0].ast); }
+    else {
+        for $/.list { $past.push($_.ast); }
     }
     make $past;
 }

src/NQP/Actions.pm

@@ -7,7 +7,8 @@ NQP::Grammar.O(':prec<w=>, :assoc<left>',  '%exponentiation');
 NQP::Grammar.O(':prec<v=>, :assoc<unary>', '%symbolic_unary');
 NQP::Grammar.O(':prec<u=>, :assoc<left>',  '%multiplicative');
 NQP::Grammar.O(':prec<t=>, :assoc<left>',  '%additive');
-NQP::Grammar.O(':prec<i=>, :assoc<right>',  '%assignment');
+NQP::Grammar.O(':prec<r=>, :assoc<list>',  '%concatenation'); 
+NQP::Grammar.O(':prec<i=>, :assoc<right>', '%assignment');
 
 method TOP($/) { make $<EXPR>.ast; }
 
@@ -16,7 +17,7 @@ method term:sym<value>($/) { make $<value>.ast; }
 method circumfix:sym<( )>($/) { make $<EXPR>.ast; }
 
 method postcircumfix:sym<[ ]>($/) {
-    make PAST::Var.new( 0, $<EXPR>.ast , :scope('keyed_int') );
+    make PAST::Var.new( $<EXPR>.ast , :scope('keyed_int') );
 }
 
 method value($/) {

src/NQP/Grammar.pm

@@ -13,6 +13,7 @@ token infix:sym<%>  { $<sym>=['%']  <O('%multiplicative, :pirop<mod>')> }
 token infix:sym<+>  { $<sym>=['+']  <O('%additive      , :pirop<add>')> }
 token infix:sym<->  { $<sym>=['-']  <O('%additive      , :pirop<sub>')> }
 token infix:sym<=>  { $<sym>=['=']  <O('%assignment')> }
+token infix:sym<~>  { $<sym>=['~']  <O('%concatenation')> }
 
 token prefix:sym<-> { $<sym>=['-']  <O('%symbolic_unary')> }
 token prefix:sym<--> { $<sym>=['--'] <O('%autoincrement')> }

src/cheats/hll-grammar.pir

@@ -377,6 +377,7 @@ An operator precedence parser.
   term_loop:
     here = here.termish()
     unless here goto fail
+    termish = 'termish'
     .local pmc term
     term = here.'MATCH'()
     push termstack, term
@@ -499,13 +500,14 @@ An operator precedence parser.
     termstack = find_lex '@termstack'
     opstack = find_lex '@opstack'
 
-    .local pmc op
+    .local pmc op, opOPER, opO
     .local string opassoc
     op = pop opstack
-    $P0 = op['OPER']
-    $P0 = $P0['O']
-    opassoc = $P0['assoc']
+    opOPER = op['OPER']
+    opO = opOPER['O']
+    opassoc = opO['assoc']
     if opassoc == 'unary' goto op_unary
+    if opassoc == 'list' goto op_list
   op_infix:
     .local pmc right, left
     right = pop termstack
@@ -514,6 +516,7 @@ An operator precedence parser.
     op[1] = right
     self.'!reduce'('EXPR', 'INFIX', op)
     goto done
+
   op_unary:
     .local pmc arg, afrom, ofrom
     arg = pop termstack
@@ -528,6 +531,27 @@ An operator precedence parser.
     self.'!reduce'('EXPR', 'POSTFIX', op)
     goto done
 
+  op_list:
+    .local string sym
+    sym = opOPER['sym']
+    arg = pop termstack
+    unshift op, arg
+  op_sym_loop:
+    unless opstack goto op_sym_done
+    $P0 = opstack[-1]
+    $P0 = $P0['OPER']
+    $S0 = $P0['sym']
+    if sym != $S0 goto op_sym_done
+    arg = pop termstack
+    unshift op, arg
+    $P0 = pop opstack
+    goto op_sym_loop
+  op_sym_done:
+    arg = pop termstack
+    unshift op, arg
+    self.'!reduce'('EXPR', 'LIST', op)
+    goto done
+
   done:
     push termstack, op
 .end