Predicator.Visitors.InstructionsVisitor (predicator v2.2.0)

Visitor that converts AST nodes to stack machine instructions.

This visitor implements post-order traversal to generate instruction lists that can be executed by the stack-based evaluator. Instructions are generated in the correct order for stack-based evaluation.

Examples

iex> ast = {:literal, 42}
iex> Predicator.Visitors.InstructionsVisitor.visit(ast, [])
[["lit", 42]]

iex> ast = {:identifier, "score"}
iex> Predicator.Visitors.InstructionsVisitor.visit(ast, [])
[["load", "score"]]

iex> ast = {:comparison, :gt, {:identifier, "score"}, {:literal, 85}}
iex> Predicator.Visitors.InstructionsVisitor.visit(ast, [])
[["load", "score"], ["lit", 85], ["compare", "GT"]]

iex> ast = {:logical_and, {:literal, true}, {:literal, false}}
iex> Predicator.Visitors.InstructionsVisitor.visit(ast, [])
[["lit", true], ["lit", false], ["and"]]

iex> ast = {:function_call, "len", [{:identifier, "name"}]}
iex> Predicator.Visitors.InstructionsVisitor.visit(ast, [])
[["load", "name"], ["call", "len", 1]]

Summary

Functions

visit(ast_node, opts \\ [])

Visits an AST node and returns stack machine instructions.

Functions

visit(ast_node, opts \\ [])

@spec visit(
  Predicator.Parser.ast(),
  keyword()
) :: [[binary() | term()]]

Visits an AST node and returns stack machine instructions.

Uses post-order traversal to ensure operands are pushed onto the stack before operators are applied.

Parameters

ast_node - The AST node to convert to instructions
opts - Optional visitor options (currently unused)

Returns

List of instructions in the format [["operation", ...args]]