blockly > BasicCursor > getPreviousNode_

BasicCursor.getPreviousNode_() method

Reverses the pre order traversal in order to find the previous node. This will allow a user to easily navigate the entire Blockly AST without having to go in and out levels on the tree.


protected getPreviousNode_(node: ASTNode | null, isValid: (p1: ASTNode | null) => boolean): ASTNode | null;


Parameter Type Description
node ASTNode | null The current position in the AST.
isValid (p1: ASTNode | null) => boolean A function true/false depending on whether the given node should be traversed.


ASTNode | null

The previous node in the traversal or null if no previous node exists.