Added numeric-for list comprehension

1 files changed, 23 insertions, 0 deletions

diff --git a/lib/collections.nom b/lib/collections.nom
index ac1b019..a2ee0cc 100644
--- a/lib/collections.nom
+++ b/lib/collections.nom
@@ -75,6 +75,29 @@ immediately
                 end)()
     parse [%expression for all %iterable] as: %expression for % in %iterable
 
+    compile [..]
+        %expression for %index from %start to %stop via %step
+        %expression for %index from %start to %stop by %step
+    ..to
+        assume ((%index's "type") is "Var") or barf ".."
+            List comprehension has the wrong type for the loop variable. Expected Var, but got: \(%index's "type")
+        return {..}
+            expr:".."
+                (function()
+                    local comprehension = {};
+                    for \(%index as lua expr)=\(%start as lua expr),\(%stop as lua expr),\(%step as lua expr) do
+                        comprehension[\(%index as lua expr)] = \(%expression as lua expr);
+                    end
+                    return comprehension;
+                end)()
+    parse [%expression for all ] as: %expression for % in %iterable
+    parse [%expression for %var from %start to %stop] as: %expression for %var from %start to %stop via 1
+    parse [..]
+        %expression for all %start to %stop by %step
+        %expression for all %start to %stop via %step
+    ..as: %expression for % from %start to %stop via %step
+    parse [%expression for all %start to %stop] as: %expression for all %start to %stop via 1
+
     compile [%expression for %key = %value in %iterable] to
         assume ((%key's "type") is "Var") or barf ".."
             List comprehension has the wrong type for the key loop variable. Expected Var, but got: \(%key's "type")