/// <summary>
/// Helper for generating the call to a builtin function. This is used for calls from built-in method
/// descriptors and built-in functions w/ and w/o a bound instance.
///
/// This provides all sorts of common checks on top of the call while the caller provides a delegate
/// to do the actual call. The common checks include:
/// check for generic-only methods
/// reversed operator support
/// transforming arguments so the default binder can understand them (currently user defined mapping types to PythonDictionary)
/// returning NotImplemented from binary operators
/// Warning when calling certain built-in functions
///
/// </summary>
/// <param name="call">The call binder we're doing the call for</param>
/// <param name="codeContext">An expression which points to the code context</param>
/// <param name="function">the meta object for the built in function</param>
/// <param name="hasSelf">true if we're calling with an instance</param>
/// <param name="args">The arguments being passed to the function</param>
/// <param name="functionRestriction">A restriction for the built-in function, method desc, etc...</param>
/// <param name="bind">A delegate to perform the actual call to the method.</param>
internal DynamicMetaObject /*!*/ MakeBuiltinFunctionCall(DynamicMetaObjectBinder /*!*/ call, Expression /*!*/ codeContext, DynamicMetaObject /*!*/ function, DynamicMetaObject /*!*/[] args, bool hasSelf, BindingRestrictions /*!*/ functionRestriction, Func <DynamicMetaObject /*!*/[] /*!*/, BindingResult /*!*/> bind)
{
DynamicMetaObject res = null;
// if we have a user defined operator for **args then transform it into a PythonDictionary
DynamicMetaObject translated = TranslateArguments(call, codeContext, new DynamicMetaObject(function.Expression, functionRestriction, function.Value), args, hasSelf, Name);
if (translated != null)
{
return(translated);
}
// swap the arguments if we have a reversed operator
if (IsReversedOperator)
{
ArrayUtils.SwapLastTwo(args);
}
// do the appropriate calling logic
BindingResult result = bind(args);
// validate the result
BindingTarget target = result.Target;
res = result.MetaObject;
if (target.Overload != null && target.Overload.IsProtected)
{
// report an error when calling a protected member
res = new DynamicMetaObject(
BindingHelpers.TypeErrorForProtectedMember(
target.Overload.DeclaringType,
target.Overload.Name
),
res.Restrictions
);
}
else if (IsBinaryOperator && args.Length == 2 && IsThrowException(res.Expression))
{
// Binary Operators return NotImplemented on failure.
res = new DynamicMetaObject(
Ast.Property(null, typeof(PythonOps), "NotImplemented"),
res.Restrictions
);
}
else if (target.Overload != null)
{
// Add profiling information for this builtin function, if applicable
IPythonSite pythonSite = (call as IPythonSite);
if (pythonSite != null)
{
var pc = pythonSite.Context;
var po = pc.Options as PythonOptions;
if (po != null && po.EnableProfiler)
{
Profiler profiler = Profiler.GetProfiler(pc);
res = new DynamicMetaObject(
profiler.AddProfiling(res.Expression, target.Overload.ReflectionInfo),
res.Restrictions
);
}
}
}
// add any warnings that are applicable for calling this function
WarningInfo info;
if (target.Overload != null && BindingWarnings.ShouldWarn(PythonContext.GetPythonContext(call), target.Overload, out info))
{
res = info.AddWarning(codeContext, res);
}
// finally add the restrictions for the built-in function and return the result.
res = new DynamicMetaObject(
res.Expression,
functionRestriction.Merge(res.Restrictions)
);
// The function can return something typed to boolean or int.
// If that happens, we need to apply Python's boxing rules.
if (res.Expression.Type.IsValueType())
{
res = BindingHelpers.AddPythonBoxing(res);
}
else if (res.Expression.Type == typeof(void))
{
res = new DynamicMetaObject(
Expression.Block(
res.Expression,
Expression.Constant(null)
),
res.Restrictions
);
}
return(res);
}
