Implement sass variable environment access

Sass.xs

@@ -1220,6 +1220,48 @@ get_callee_column(back)
     OUTPUT:
              RETVAL
 
+SV*
+get_callee_var(name, back)
+            const char* name
+            size_t back
+    CODE:
+    {
+
+        SV* comp = get_sv("CSS::Sass::compiler", GV_ADDWARN);
+        struct Sass_Compiler* compiler = INT2PTR(struct Sass_Compiler*, SvIV(comp));
+        size_t idx = sass_compiler_get_callee_stack_size(compiler);
+        if (idx <= back) croak("Callee stack access out of boundary");
+        Sass_Callee_Entry entry = sass_compiler_get_callee_entry(compiler, idx - back - 1);
+        Sass_Env_Frame env = sass_callee_get_env(entry);
+        union Sass_Value* value = sass_env_get_lexical(env, name);
+        if (value == NULL) RETVAL = new_sv_sass_null();
+        else RETVAL = sass_value_to_sv(value);
+
+    }
+    OUTPUT:
+             RETVAL
+
+SV*
+set_callee_var(name, value, back)
+            const char* name
+            SV* value
+            size_t back
+    CODE:
+    {
+
+        SV* comp = get_sv("CSS::Sass::compiler", GV_ADDWARN);
+        struct Sass_Compiler* compiler = INT2PTR(struct Sass_Compiler*, SvIV(comp));
+        size_t idx = sass_compiler_get_callee_stack_size(compiler);
+        if (idx <= back) croak("Callee stack access out of boundary");
+        Sass_Callee_Entry entry = sass_compiler_get_callee_entry(compiler, idx - back - 1);
+        Sass_Env_Frame env = sass_callee_get_env(entry);
+        sass_env_set_lexical(env, name, sv_to_sass_value(value));
+        RETVAL = new_sv_sass_null();
+
+    }
+    OUTPUT:
+             RETVAL
+
 SV*
 libsass_version()
     CODE:

lib/CSS/Sass.pm

@@ -45,6 +45,8 @@ our @EXPORT_OK = qw(
 	get_callee_path
 	get_callee_line
 	get_callee_column
+	get_callee_var
+	set_callee_var
 	get_import_abs_path
 	get_import_imp_path
 	get_import_stack_size
@@ -626,7 +628,7 @@ L<The CSS::Sass Home Page|https://github.com/sass/perl-libsass>
 
 =head1 AUTHOR
 
-David Caldwell E<lt>david@porkrind.orgE<gt>  
+David Caldwell E<lt>david@porkrind.orgE<gt>
 Marcel Greter E<lt>perl-libsass@ocbnet.chE<gt>
 
 =head1 LICENSE