AstTraverse

Introduction

A implementation of treat erlang abstract format with traversable like api

traverse :: (a -> f b) -> t a -> f (t b)

map_m :: (a -> m b) -> t a -> m (t b)

here is my mutation map_m

map_m :: (pre | post -> a -> m b) -> t a -> m (t b)

where

a :: node
b :: node
t a :: ast
t b :: ast 

Without monad

mapfold :: (pre | post, -> node -> state -> (node, state)) -> init_state -> ast -> (ast, state)

map_with_state :: (pre | post, -> node -> state -> (node, state)) -> init_state -> ast -> ast

map :: (pre | post -> node -> node) -> ast -> ast

reduce :: (pre | post -> node -> state -> state) -> ast -> init_state -> state

explanation

pre means this node is traversed before it's children

post means this node is traversed after it's children

every node is travered both in pre and post type

so it's a mutation travserse

traverse order

[form1, form2, [([pattern1, pattern2], [[guard1]], [expression1, expression2]) = function_clause1] = form3] is traversed in such order

(leaf, form1)

(leaf, form2)

(pre,  form3)
    
(pre,  function_clause1)
    
(leaf, pattern1)
    
(leaf, pattern2)
    
(leaf, guard_test1)
    
(leaf, expression1)

(leaf, expression2)
 
(post, fun_cluase,  funnction_clause1)
    
(post, form, form3)

Astranaut

astranaut is a better ast_traverse with quote and macro support
https://github.com/slepher/astranaut