C# Class IronPython.Runtime.Binding.PythonProtocol

Produces an error message for the provided message and type names. The error message should contain string formatting characters ({0}, {1}, etc...) for each of the type names.

Helper to convert all of the arguments to their known types.

calls __coerce__ for old-style classes and performs the operation if the coercion is successful.

Helper to get the symbols for __*item__ and __*slice__ based upon if we're doing a get/set/delete and the minimum number of arguments required for each of those.

Gets the arguments that need to be provided to __*item__ when we need to pass a slice object.

Creates a rule for the contains operator. This is exposed via "x in y" in IronPython. It is implemented by calling the __contains__ method on x and passing in y. If a type doesn't define __contains__ but does define __getitem__ then __getitem__ is called repeatedly in order to see if the object is there. For normal .NET enumerables we'll walk the iterator and see if it's present.

Python has three protocols for slicing: Simple Slicing x[i:j] Extended slicing x[i,j,k,...] Long Slice x[start:stop:step] The first maps to __*slice__ (get, set, and del). This takes indexes - i, j - which specify the range of elements to be returned. In the slice variants both i, j must be numeric data types. The 2nd and 3rd are both __*item__. This receives a single index which is either a Tuple or a Slice object (which encapsulates the start, stop, and step values) This is in addition to a simple indexing x[y]. For simple slicing and long slicing Python generates Operators.*Slice. For the extended slicing and simple indexing Python generates a Operators.*Item action. Extended slicing maps to the normal .NET multi-parameter input. So our job here is to first determine if we're to call a __*slice__ method or a __*item__ method.

Helper to handle a comparison operator call. Checks to see if the call can return NotImplemented and allows the caller to modify the expression that is ultimately returned (e.g. to turn __cmp__ into a bool after a comparison)

Makes the comparison rule which returns an int (-1, 0, 1). TODO: Better name?

Checks if a coercion check should be performed. We perform coercion under the following situations: 1. Old instances performing a binary operator (excluding rich comparisons) 2. User-defined new instances calling __cmp__ but only if we wouldn't dispatch to a built-in __coerce__ on the parent type This matches the behavior of CPython.