rubyish - handle revised nqp::for iteration on hashes

nqp::for on a hash object now returns an iterator object. nqp::iter_key and
nqp::iter_val are used to extract the key and value respectively.

examples/rubyish/README.md

@@ -27,7 +27,7 @@ Implemented:
 - statement modifiers `if` `unless`, `while`, `until` e.g.: `puts 42 if true`
 - basic arrays and hashes
 - for loops on arrays: `for val in [10, 20, 30] do puts val end`
-- for loops on hash keys: `h = {'a'=>10, 'b'=>20}; for k in h do puts h{k} end`
+- for loops on hash pairs: `h = {'a'=>10, 'b'=>20}; for kv in h do puts value k end`
 - lambda blocks/closures: `def make_counter(n,incr) ; n-=incr; lambda { n += incr }; end`
 - lightweight eRuby like templating, see [template.rbi](examples-rubyish/template.rbi)
 - heredocs, literal `<<EOF ... EOF` and interpolating `<<"END" ... END`
@@ -59,6 +59,13 @@ Strings and truth values are Perlish rather than Rubyish:
 - hash dereferencing is via angle braces: `puts fruit<apples>` or
 curlies `puts fruit{'bananas'}`
 
+hash iteration is by pairs. The `key` and `value` built-ins are used for dereferencing
+```
+    for item in {"apples" => 20, "bananas" => 35, "potatos" => 12}
+        puts" #{key item} are #{value item} cents per Kg"
+    end
+```
+
 nqp op-codes can be called like regular functions. E.g.
 ```
     puts nqp::if(2+2 == 4, 'yup', 'nope' )

examples/rubyish/rubyish.nqp

@@ -71,8 +71,8 @@ grammar Rubyish::Grammar is HLL::Grammar {
         [ <stmt=.stmtish>? ] *%% [<.separator>|<stmt=.template-chunk>]
     }
 
-    token stmtish {
-        <stmt> [:s<hs> <modifier> <EXPR>]?
+    token stmtish {:s<hs>
+        <stmt> [ <modifier> <EXPR>]?
     }
 
     token modifier {if|unless|while|until}
@@ -147,6 +147,9 @@ grammar Rubyish::Grammar is HLL::Grammar {
         %builtins := nqp::hash(
             'abort',  'die',
             'exit',   'exit',
+            'key',    'iterkey_s',
+            'delete', 'deletekey',
+            'value',  'iterval',
             'print',  'print',
             'puts',   'say',
             'sleep',  'sleep',

examples/rubyish/t/hashs.t

@@ -7,19 +7,19 @@ h_idx = 'c'
 puts "#{h{h_idx} == 30? 'ok' : 'nok'} 3 - h{c_idx}"
 puts "#{h{'d'} == 100? 'ok' : 'nok'} 4 - h{'d'}"
 
-nqp::deletekey(h, 'd')
+delete(h, 'd')
 
-for key in h do
-    puts "ok #{ h{key} / 10  +  4 } - hash key iteration (#{key})"
+for kv in h do
+    puts "ok #{value(kv) / 10  +  4 } - hash key iteration (#{key kv})"
 end
 
 h<d> = ['nok','ok']
 puts "#{ h<d>[1] } 8 - HoA"
 
 def test_hash_args(x, h_args)
     puts "ok #{ x } - fixed arg"
-    for k in h_args do
-       puts "ok #{ h_args{k} } - hash slurpy arg (#{k})"
+    for kv in h_args do
+       puts "ok #{ value kv } - hash slurpy arg (#{key kv})"
     end
 end