knit_script.knit_script_interpreter.expressions.accessors module

Used to access attributes from instances in code.

This module provides the Attribute_Accessor_Expression class, which handles attribute access operations for knit script expressions. It supports accessing attributes from both knit script objects and underlying Python objects, including method calls, property access, and specialized handling for machine and sheet-specific needle collections.

class Attribute_Accessor_Expression(parser_node, parent_path, attribute)[source]

Bases: Expression

Accesses attributes of expression either from knit-script or underlying python.

This class handles complex attribute access operations in knit script, supporting both direct attribute access and method calls. It can access attributes from Python objects as well as specialized knit script objects like machines and sheet identifiers. The class supports chained attribute access and provides specialized handling for needle set expressions.

is_method_call

True if the attribute being accessed is a method call.

Type:: bool

parent

List of parent expressions in the access chain.

Type:: list[Expression]

attribute

The attribute being accessed from the parent.

Type:: Expression

Parameters:

parser_node (LRStackNode)
parent_path (list[Expression] | Expression)
attribute (Expression)

__init__(parser_node, parent_path, attribute)[source]

Initialize the Attribute_Accessor_Expression.

Parameters:

parser_node (LRStackNode) – The parser node from the parse tree.
parent_path (list[Expression] | Expression) – The expression to access an attribute from. Can be a single expression or a chain of expressions.
attribute (Expression) – The attribute of the parent expression. May produce more nested accessors.

parent_path()[source]

Get the path to parent value as a dot-separated string.

Returns:: Path to parent value with expressions separated by dots.
Return type:: str

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 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

evaluate(context)[source]

Evaluate the expression to access the specified attribute.

Parameters:: context (Knit_Script_Context) – The current context of the knit_script_interpreter.
Returns:: The accessed attribute value from the parent expression.
Return type:: Any
Raises:: AttributeError – If the attribute cannot be accessed from the parent object.