Migrated source code from Simantics SVN

[simantics/platform.git] / bundles / org.simantics.scl.compiler / src / org / simantics / scl / compiler / internal / deriving / DerivingUtils.java

diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/deriving/DerivingUtils.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/deriving/DerivingUtils.java
new file mode 100644 (file)
index 0000000..dc37950
--- /dev/null
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/deriving/DerivingUtils.java
@@ -0,0 +1,28 @@
+package org.simantics.scl.compiler.internal.deriving;\r
+\r
+import org.simantics.scl.compiler.internal.parsing.types.TApplyAst;\r
+import org.simantics.scl.compiler.internal.parsing.types.TTupleAst;\r
+import org.simantics.scl.compiler.internal.parsing.types.TVarAst;\r
+import org.simantics.scl.compiler.internal.parsing.types.TypeAst;\r
+\r
+class DerivingUtils {\r
+    \r
+    static TVarAst getHeadType(TypeAst typeAst) {\r
+        while(true) {\r
+            if(typeAst instanceof TApplyAst)\r
+                typeAst = ((TApplyAst)typeAst).function;\r
+            else if(typeAst instanceof TVarAst)\r
+                return (TVarAst)typeAst;\r
+            else if(typeAst instanceof TTupleAst) {\r
+                TTupleAst tuple = (TTupleAst)typeAst;\r
+                if(tuple.components.length == 1)\r
+                    typeAst = tuple.components[0];\r
+                else\r
+                    return null;\r
+            }\r
+            else\r
+                return null;\r
+        }\r
+    }\r
+    \r
+}\r