Add implicit collection cast

README.md

@@ -182,10 +182,10 @@ Python: (lambda x: x.foo)(OCLTuple(foo='abc'))
 OCL:    ParameterDirectionKind::inout
 Python: ParameterDirectionKind.inout
 
-OCL:    (if nestingClass > null then null
+OCL:    (if nestingClass <> null then null
         else
         let b:BehavioredClassifier = self.behavioredClassifier(self.owner) in
-                if b.oclIsKindOf(Behavior) and b.oclAsType(Behavior).context > null then
+                if b.oclIsKindOf(Behavior) and b.oclAsType(Behavior).context <>> null then
                         b.oclAsType(Behavior).context
                                 else b endif endif)
 Python: (None if nestingClass > None else (lambda b: b.context if isinstance(b, Behavior) and b.context > None else b)(self.behavioredClassifier(self.owner)))
@@ -216,5 +216,5 @@ Here is a demo on how to use it.
 
 Currently, some expressions are not well recognized, or not properly compiled:
 
-* `obj->operation()`: in the specification, `->` acts as an automatic wrapper to a `Sequence` if `obj` is not a collection. Currently, PyEcoreOCL doesn't consider this automatic wrapping.
+* `obj->operation()`: in the specification, `->` acts as an automatic wrapper to a `Sequence` if `obj` is not a collection. Currently, PyEcoreOCL doesn't consider this automatic wrapping for strict mode, but partially implement it for the normal mode.
 * `collection->collect(attr)`: when there is no variable that is considered by the lambda inside collection operations, by default `attr` should be considered as attribute of an implicit `self` variable representing at each iteration one of the elements of `collection`. Currently, this is not supported, and it's not sure it will be for inline OCL. To overcome this, it's currently necessary to explicitally name the variable inside the lambda `collection->collect(e | e.attr)`.

magic_ocl/main.py

@@ -78,7 +78,7 @@ def ocl2python(tokens: Iterable[TokenInfo], mode: str):
 
 def preprocess(data: str, mode: str="normal"):
     return f"""
-import itertools, collections
+import itertools, collections, typing
 import pyecoreocl.runtime as ocl
 {untokenize(ocl2python(generate_tokens(StringIO(data).readline), mode=mode))}
 """

pyecoreocl/dummy_rules/collections_rules.py

@@ -205,24 +205,34 @@ def rule_excludes_all(emitter, ctx):
     emitter.inline(")")
 
 
+def dispatch_iterable(emitter, expression):
+    if emitter.mode == "strict":
+        emitter.visit(expression)
+        return
+
+    emitter.inline("((lambda x: x if isinstance(x, typing.Iterable) and not isinstance(x, (bytes, str)) else (x,))(")
+    emitter.visit(expression)
+    emitter.inline("))")
+
+
 @collection_rule
 def rule_as_sequence(emitter, ctx):
     emitter.inline("list(")
-    emitter.visit(ctx.expression)
+    dispatch_iterable(emitter, ctx.expression)
     emitter.inline(")")
 
 
 @collection_rule
 def rule_as_set(emitter, ctx):
     emitter.inline("set(")
-    emitter.visit(ctx.expression)
+    dispatch_iterable(emitter, ctx.expression)
     emitter.inline(")")
 
 
 @collection_rule
 def rule_as_bag(emitter, ctx):
     emitter.inline("list(")
-    emitter.visit(ctx.expression)
+    dispatch_iterable(emitter, ctx.expression)
     emitter.inline(")")