Skip to content

TODO.md

Latest commit

 

History

History
35 lines (23 loc) · 1.28 KB

TODO.md

File metadata and controls

35 lines (23 loc) · 1.28 KB

TODO

Refactor / rebuild parser

Goal:

  1. Separate tokenize and parsing
  2. Use Djikstra's Shunting Yard algorithm to convert the Infix token list notation to Postfix, and use it to build the AST instead the today's loop-based parser

Inspiration: c't Author Oliver Lau's APC::

Tokenizing

  • create a tokenize function, based on the today's _do_parse() function
  • create Token objects with metadata (type, value, position, etc.)
  • input is still a string, but the result is an array of tokens, instead of a string

Parsing

  • operate on token list
  • implement Shunting Yard algorithm
  • work on Token list, create Expression objects on the go
  • create AST from Shunting Yard output
  • goal: as today, one single top level expression object as output

Get rid of the short varibale form

Get rid of the short form 3x instead of 3*x: It makes variable handling and parsing much more complex, and makes it necessary to explicitly mark longer variable names. Today, longer variable names are surrounded by []. As I want to implement lists/arrays in formulas, and [] is the common syntax for lists, I will introduce a breaking change in the next major release, removing this form.