Constructing syntax trees

[Roadagain]

i guess the trees will be like this constructed by values and binary operators.

data Tree token = Leaf token | Node (Tree token) token (Tree token)

i have 2 questions:

1. is it cool?
2. how should we configure prefix and postfix operators (include unary operators)?

[Roadagain]

i guess constructing unary operators as Unary token (Tree token) and renaming Node to Binary. then it changes like this:

data Tree token = Leaf token |
                  Binary (Tree token) token (Tree token) |
                  Unary token (Tree token)

if we use this construction, should we rename Leaf too?

[Iruyan-Zak]

@Roadagain

1. is it cool?

agree to your idea completely.

2. how should we configure prefix and postfix operators (include unary operators)?

Your last comment is better. In my head, the order between prefix and suffix operators is suffix priority.

3. should we rename Leaf too?

I think it's no problem naming. Because Binary is regarded as an omission of "binary tree" and Unary too, so Leaf means "the leaf of a binary or unary tree." Further, Tree is general naming and usable generally, so Leaf should be also general one. (or rename Tree.)

[Roadagain]

constructing trees has been done by a2a266d, but it doesn't seem beautiful.

i have two ideas:

1. rewrite Tree (with StateT?)
2. reconfigure trees

if you have something else, write here.

[Roadagain]

bugfix has been done, then i wish to implement prioritized construct. i hope to add a new field holds priority (maybe Int) to Token.

[Iruyan-Zak]

Cannot you deal with it with an associated array (operator => priority)?

[Roadagain]

well... i will try it.

[Roadagain]

succeeded. is there any job not-implemented?

[Iruyan-Zak]

Great job. roll function looks cool solution for me!!!

btw, I was surprised by returning an unary tree from binary function...

[Iruyan-Zak]

If you think it is a no important problem, please create PR now.

[Roadagain]

i've forgotten it is implemented to make easier to test. i will add an integrated function to construct syntax trees.

[Roadagain]

i guess no functions can surprise u already. can i create pull-req?