knit_script.knit_script_interpreter.statements.return_statement module

Used for storing results of function returns.

This module provides the Return_Statement class, which handles function return operations in knit script programs. It evaluates return expressions and manages the return value propagation through the scope hierarchy.

class Return_Statement(parser_node, exp)

Bases: Statement

Statement that breaks out of function scope with a returned value.

When executed, this statement evaluates an expression and sets it as the return value for the current function, then signals that execution should exit the function scope. The return statement provides the mechanism for functions to produce results and terminate execution early.

The return value is propagated through the scope hierarchy to reach the appropriate function scope, and execution of the current function terminates immediately after the return statement is processed.

_expression

The expression to evaluate and return as the function result.

Type:

Expression

__init__(parser_node, exp)

Initialize a return statement.

Parameters:

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

• exp (Expression) – The expression to evaluate and return as the function result.

execute(context)

Execute the return by setting the return value and return flag.

Evaluates the return expression and stores the result in the current variable scope, then sets the return flag to signal that function execution should terminate immediately.

Parameters:

context (Knit_Script_Context) – The current execution context of the knit script interpreter.

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 execute methods in subclasses with appropriate error handling and debugging decorators.

This method is called whenever a class inherits from Statement. It checks if the subclass defines its own execute method and wraps it with the appropriate decorators

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