swap arguments in polyglot.export_value

Author: timfel

CHANGELOG.md

@@ -7,6 +7,7 @@ language runtime. The main focus is on user-observable behavior of the engine.
 
 * Add `java.add_to_classpath` API to dynamically extend the host class path
 * Allow write access to main module bindings for embedder
+* Swap arguments for `polyglot.export_value` to use the more natural (name, value) order and deprecate the previous argument order.
 
 ## Version 20.0.0 beta 1
 

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/JavaModuleBuiltins.java

@@ -116,7 +116,7 @@ Object type(PString name) {
     abstract static class AddToClassPathNode extends PythonBuiltinNode {
         @Specialization
         PNone add(VirtualFrame frame, Object[] args,
-                  @Cached CastToStringNode castToString) {
+                        @Cached CastToStringNode castToString) {
             Env env = getContext().getEnv();
             if (!env.isHostLookupAllowed()) {
                 throw raise(PythonErrorType.NotImplementedError, "host access is not allowed");

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/PolyglotModuleBuiltins.java

@@ -231,15 +231,15 @@ protected boolean isMimeType(String lang) {
         }
     }
 
-    @Builtin(name = "export_value", minNumOfPositionalArgs = 1, parameterNames = {"value", "name"})
+    @Builtin(name = "export_value", minNumOfPositionalArgs = 1, parameterNames = {"name", "value"})
     @GenerateNodeFactory
     public abstract static class ExportSymbolNode extends PythonBuiltinNode {
         @Child private GetAttributeNode getNameAttributeNode;
         @Child private CastToStringNode castToStringNode;
 
-        @Specialization
+        @Specialization(guards = "!isString(value)")
         @TruffleBoundary
-        public Object exportSymbol(Object value, String name) {
+        public Object exportSymbolKeyValue(String name, Object value) {
             Env env = getContext().getEnv();
             if (!env.isPolyglotAccessAllowed()) {
                 throw raise(PythonErrorType.NotImplementedError, "polyglot access is not allowed");
@@ -248,6 +248,23 @@ public Object exportSymbol(Object value, String name) {
             return value;
         }
 
+        @Specialization(guards = "!isString(value)")
+        @TruffleBoundary
+        public Object exportSymbolValueKey(Object value, String name) {
+            PythonLanguage.getLogger().warning("[deprecation] polyglot.export_value(value, name) is deprecated " +
+                            "and will be removed. Please swap the arguments.");
+            return exportSymbolKeyValue(name, value);
+        }
+
+        @Specialization(guards = "isString(arg1)")
+        @TruffleBoundary
+        public Object exportSymbolAmbiguous(Object arg1, String arg2) {
+            PythonLanguage.getLogger().warning("[deprecation] polyglot.export_value(str, str) is ambiguous. In the future, this will " +
+                            "default to using the first argument as the name and the second as value, but now it " +
+                            "uses the first argument as value and the second as the name.");
+            return exportSymbolValueKey(arg1, arg2);
+        }
+
         @Specialization
         @TruffleBoundary
         public Object exportSymbol(PFunction fun, @SuppressWarnings("unused") PNone name) {