Parameter Aliases

Parameters can have an alias. This is useful when a parameter name clashes with a builtin python keyword(i.e. list, dict, id, type). To give a parameter an alias, add “alias=<parameter_alias>” as it’s type hint.

I.E.

def my_func(hub, id_: "alias=id"):
    ...

This function can now be called one of three ways:

• With a positional argument: hub._.my_func(“value”)
• With the parameter as defined hub._.my_func(id_=”value”)
• With the the paramater alias hub._.my_func(id=”value”)

Whether “value” is passed as a positional argument, as a keyword argument, or with the keyword argument alias, it will populate the “id_” variable.

If the variable has a regular type-hint, you can make the whole parameter’s type hint a tuple. The first value in the tuple is the traditional type of the parameter. The second value is a string that contains the alias notation.

I.E.

def my_func(hub, id_: (str, "alias=id")):
    ...

Multiple aliases can be defined for a single parameter. Either as a tuple:

def my_func(hub, id_: ("alias=id", "alias=other")):
    ...

Or in a single string:

def my_func(hub, id_: "alias=id, alias=other"):
    ...

If aliases conflict with other arguments, or if the same alias is used for multiple parameters in the same function, then a SyntaxError will be thrown.

Retrieving Param Aliases

Parameter Aliases are part of the contracted object that represent a function. With the function ref on the hub, you can access the aliases available to a function:

def my_func(hub, id_: "alias=id, alias=other"):
    ...


hub._.my_func.param_aliases == {"id_": {"id_", "id", "other"}}