From eaa4deb2738645dfe7c1228027227c5d16117314 Mon Sep 17 00:00:00 2001
From: pmichaud <pmichaud@pobox.com>
Date: Wed, 26 May 2010 00:53:18 -0500
Subject: [PATCH] Add a more lexically-aware interactive REPL.  Still some
 tweaks wanted.

---
 build/PARROT_REVISION       |  2 +-
 src/HLL/Compiler.pm         | 22 ++++++++++++++++++++--
 src/NQP/Actions.pm          |  4 ++++
 src/cheats/hll-compiler.pir | 21 +++++++++++++++++++++
 4 files changed, 46 insertions(+), 3 deletions(-)

diff --git a/build/PARROT_REVISION b/build/PARROT_REVISION
index c4f60fa..567756d 100644
--- a/build/PARROT_REVISION
+++ b/build/PARROT_REVISION
@@ -1 +1 @@
-46979
+47014
diff --git a/src/HLL/Compiler.pm b/src/HLL/Compiler.pm
index 8c9ef2f..665e122 100644
--- a/src/HLL/Compiler.pm
+++ b/src/HLL/Compiler.pm
@@ -108,17 +108,26 @@ class HLL::Compiler is PCT::HLLCompiler {
 
             # Set the current position of stdout for autoprinting control
             my $*AUTOPRINTPOS := pir::tell__IP(pir::getstdout__P());
+            our $interactive_ctx;
+            our %interactive_pad;
+            my $*CTXSAVE := self;
+            my $*MAIN_CTX;
 
             if $code {
                 $code := $code ~ "\n";
                 my $output;
                 {
-                    $output := self.eval($code, |%adverbs);
+                    $output := self.eval($code, :outer_ctx($interactive_ctx), |%adverbs);
                     CATCH {
                         pir::print(~$! ~ "\n");
                         next;
                     }
                 };
+                if pir::defined($*MAIN_CTX) {
+                    for $*MAIN_CTX.lexpad_full() {
+                        %interactive_pad{$_.key} := $_.value;
+                    }
+                }
                 next if pir::isnull($output);
 
                 if !$target {
@@ -140,7 +149,7 @@ class HLL::Compiler is PCT::HLLCompiler {
                 && %adverbs<target> eq '' {
             my $outer_ctx := %adverbs<outer_ctx>;
             if pir::defined($outer_ctx) {
-                $output[0].set_outer(pir::getattribute__PPs($outer_ctx, 'current_sub'));
+                $output[0].set_outer_ctx($outer_ctx);
             }
 
             pir::trace(%adverbs<trace>);
@@ -150,4 +159,13 @@ class HLL::Compiler is PCT::HLLCompiler {
 
         $output;
     }
+
+    method ctxsave() {
+        $*MAIN_CTX :=
+            Q:PIR {
+                $P0 = getinterp
+                %r = $P0['context';1]
+            };
+        $*CTXSAVE := 0;
+    }
 }
diff --git a/src/NQP/Actions.pm b/src/NQP/Actions.pm
index 5ad6095..8e9b3a9 100644
--- a/src/NQP/Actions.pm
+++ b/src/NQP/Actions.pm
@@ -50,6 +50,10 @@ method comp_unit($/) {
     my $mainline := $<statementlist>.ast;
     my $unit     := @BLOCK.shift;
 
+    # If our caller wants to know the mainline ctx, provide it here.
+    # (CTXSAVE is inherited from HLL::Actions.)
+    $unit.push( self.CTXSAVE() );
+
     # We force a return here, because we have other
     # :load/:init blocks to execute that we don't want
     # to include as part of the mainline.
diff --git a/src/cheats/hll-compiler.pir b/src/cheats/hll-compiler.pir
index 6a35c0c..569453a 100644
--- a/src/cheats/hll-compiler.pir
+++ b/src/cheats/hll-compiler.pir
@@ -103,3 +103,24 @@
     # return the result
     .return (ns)
 .end
+
+
+# This sub serves as a cumulative "outer context" for code
+# executed in HLL::Compiler's interactive REPL.  It's invoked
+# exactly once upon load/init to obtain a context, and its
+# default LexPad is replaced with a Hash that we can use to
+# cumulatively store outer context information.  Both the
+# context and hash are then made available via package
+# variables.
+.namespace []
+.sub '&interactive_outer' :lex :init :load
+    .local pmc ctx, pad
+    $P0 = getinterp
+    ctx = $P0['context']
+    set_global ['HLL';'Compiler'], '$interactive_ctx', ctx
+    pad = getattribute ctx, 'lex_pad'
+    $P1 = new ['Hash']
+    copy pad, $P1
+    set_global ['HLL';'Compiler'], '%interactive_pad', pad
+.end
+