From 0b8d1a00e1a62f2ba5da56b32610f5d91d2af0bb Mon Sep 17 00:00:00 2001
From: Nat Quayle Nelson <natquaylenelson@gmail.com>
Date: Mon, 7 Dec 2020 18:28:12 -0700
Subject: [PATCH] KeyValueExps allow map literals

---
 src/kiss/Kiss.hx                  | 16 ++++++++++++++--
 src/kiss/Reader.hx                |  6 ++++++
 src/test/cases/BasicTestCase.hx   |  4 ++++
 src/test/cases/BasicTestCase.kiss |  9 ++++++++-
 4 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/src/kiss/Kiss.hx b/src/kiss/Kiss.hx
index eb94370..7444049 100644
--- a/src/kiss/Kiss.hx
+++ b/src/kiss/Kiss.hx
@@ -135,8 +135,18 @@ class Kiss {
                     ECast(convert(innerExp), if (type.length > 0) Helpers.parseComplexType(type, exp) else null).withMacroPosOf(wholeExp);
              */
             case ListExp(elements):
-                var arrayDecl = EArrayDecl([for (elementExp in elements) convert(elementExp)]).withMacroPosOf(exp);
-                if (k.wrapListExps) {
+                var isMap = false;
+                var arrayDecl = EArrayDecl([
+                    for (elementExp in elements) {
+                        switch (elementExp.def) {
+                            case KeyValueExp(_, _):
+                                isMap = true;
+                            default:
+                        }
+                        convert(elementExp);
+                    }
+                ]).withMacroPosOf(exp);
+                if (!isMap && k.wrapListExps) {
                     ENew({
                         pack: ["kiss"],
                         name: "List"
@@ -148,6 +158,8 @@ class Kiss {
                 Context.parse(code, exp.macroPos());
             case FieldExp(field, innerExp):
                 EField(convert(innerExp), field).withMacroPosOf(exp);
+            case KeyValueExp(keyExp, valueExp):
+                EBinop(OpArrow, convert(keyExp), convert(valueExp)).withMacroPosOf(exp);
             default:
                 throw CompileError.fromExp(exp, 'conversion not implemented');
         };
diff --git a/src/kiss/Reader.hx b/src/kiss/Reader.hx
index c43335a..d5074c6 100644
--- a/src/kiss/Reader.hx
+++ b/src/kiss/Reader.hx
@@ -19,6 +19,7 @@ enum ReaderExpDef {
     TypedExp(path:String, exp:ReaderExp); // :type [exp]
     MetaExp(meta:String, exp:ReaderExp); // &meta [exp]
     FieldExp(field:String, exp:ReaderExp); // .field [exp]
+    KeyValueExp(key:ReaderExp, value:ReaderExp); // =>key value
 }
 
 typedef ReadFunction = (Stream) -> Null<ReaderExpDef>;
@@ -57,6 +58,9 @@ class Reader {
         // Lets you dot-access a function result without binding it to a name
         readTable["."] = (stream:Stream) -> FieldExp(nextToken(stream, "a field name"), assertRead(stream, readTable));
 
+        // Lets you construct key-value pairs for map literals or for-loops
+        readTable["=>"] = (stream:Stream) -> KeyValueExp(assertRead(stream, readTable), assertRead(stream, readTable));
+
         // Because macro keys are sorted by length and peekChars(0) returns "", this will be used as the default reader macro:
         readTable[""] = (stream) -> Symbol(nextToken(stream, "a symbol name"));
         // TODO make - A macro for numerical negation
@@ -173,6 +177,8 @@ class Reader {
                 '&$meta ${exp.def.toString()}';
             case FieldExp(field, exp):
                 '.$field ${exp.def.toString()}';
+            case KeyValueExp(keyExp, valueExp):
+                '=>${keyExp.def.toString()} ${valueExp.def.toString()}';
         }
     }
 }
diff --git a/src/test/cases/BasicTestCase.hx b/src/test/cases/BasicTestCase.hx
index a372b91..5ee5948 100644
--- a/src/test/cases/BasicTestCase.hx
+++ b/src/test/cases/BasicTestCase.hx
@@ -242,6 +242,10 @@ class BasicTestCase extends Test {
     function testCase() {
         _testCase();
     }
+
+    function testMaps() {
+        _testMaps();
+    }
 }
 
 class BasicObject {
diff --git a/src/test/cases/BasicTestCase.kiss b/src/test/cases/BasicTestCase.kiss
index 15d231a..3e815df 100644
--- a/src/test/cases/BasicTestCase.kiss
+++ b/src/test/cases/BasicTestCase.kiss
@@ -339,4 +339,11 @@
         ((Some "hey") (Assert.pass))
         (otherwise (Assert.fail)))
     (Assert.equals 5 (case (toOption 0)
-        (otherwise 5))))
\ No newline at end of file
+        (otherwise 5))))
+
+(defun _testMaps []
+    (deflocal :Map<String,String> myMap [=>"hey" "you"
+                        =>"found" "me"])
+    (Assert.equals "you" (dict-get myMap "hey"))
+    (Assert.equals "me" (dict-get myMap "found"))
+    )
\ No newline at end of file