knit_script.knit_script_interpreter.expressions.function_expressions module

Expressions associated with functions.

This module provides the Function_Call class, which handles function call expressions in knit script programs. It supports both knit script user-defined functions and Python callable objects, with parameter passing through positional and keyword arguments.

class Function_Call(parser_node, func_name, args, kwargs)

Bases: Expression

A call to a function which must return a value or result in None.

The Function_Call class handles the execution of function calls in knit script programs. It supports both user-defined knit script functions (represented by Function_Signature objects) and Python callable objects. The class manages parameter passing through both positional arguments and keyword arguments, evaluating them in the current context before passing them to the target function.

This class provides the bridge between knit script function call syntax and the underlying function execution mechanisms, whether they are knit script functions with their own scopes or Python functions integrated into the knit script environment.

kwargs

The list of assignments used to set keyword arguments.

Type:

list[Assignment]

args

The list of expressions to fill in positional arguments.

Type:

list[Expression]

func_name

The name of the function to call.

Type:

Variable_Expression

__init__(parser_node, func_name, args, kwargs)

Initialize the Function_Call.

Parameters:

• parser_node (LRStackNode) – The parser node from the parse tree.

• func_name (Variable_Expression) – Name of the function to call.

• args (list[Expression]) – The list of argument expressions to evaluate and pass as positional parameters.

• kwargs (list[Assignment]) – The list of assignments to evaluate and pass as keyword parameters.

evaluate(context)

Find function in scope, fill parameters and then execute.

Locates the function in the current variable scope, evaluates all arguments, and executes the function with the provided parameters.

Handles both knit script functions and Python callable objects.

Parameters:

context (Knit_Script_Context) – The current context of the knit_script_interpreter.

Returns:

Return value set at function scope before closing, or the result of the Python function call.

Return type:

Any

Raises:

NameError – If the function name is not defined in the current scope.

classmethod __class_getitem__(params)

Parameterizes a generic class.

At least, parameterizing a generic class is the main thing this method does. For example, for some generic class Foo, this is called when we do Foo[int] - there, with cls=Foo and params=int.

However, note that this method is also called when defining generic classes in the first place with class Foo(Generic[T]): ….

classmethod __init_subclass__(**kwargs)

Automatically wrap evaluate methods in subclasses with appropriate error handling decorator.

This method is called whenever a class inherits from Expression. It checks if the subclass defines its own evaluate method and wraps it with the appropriate decorator.

Parameters:

**kwargs (Any) – Additional keyword arguments passed to super().__init_subclass__

property file_name: str | None

Returns: str | None: The file name of the knitscript program this was parsed from or None if the program was passed as a string.

property line_number: int

Get the line number of the symbol that generated this statement.

Returns:

The line number where this element appears in the source file.

Return type:

int

property local_path: str | None

Returns: str | None: The path to the directory containing the file from which this element was parsed or None if the value was parsed from a python string.

property location: Location

Get the location of this symbol in KnitScript file.

Returns:

The location of this symbol in the source file, including file name, line number, and position information.

Return type:

Location

property location_str: str

Returns: str: The string referencing the line number and possible file name information about this element.

property position_context: str

The position context string is the string from the knitscript program from which this element was parsed. The context string will begin at the start of this element and continue to the end of the line of knitscript or a semicolon on new line are reached.

Returns:

The string used to contextualize this element in the knitscript program.

Return type:

str