Add string manipulation capability

[kanaka]

Right now there is no cross-implementation way to manipulate (index, slice, etc).

In Clojure, strings are treated as sequences of characters and so sequence functions operate on them. However, as a simple initial (or maybe final) step, simply adding a seq function that turns a string into a list of single character strings would allow manipulation using normal sequence functions (str will already concatenate a sequence of character strings into a single string).

For now I'm thinking this would be an optional stepA function.

So here is the list for adding a seq function:

• awk
• bash
• c
• d
• clojure
• coffee
• cpp
• crystal
• cs
• erlang
• elixir
• es6
• factor
• forth
• fsharp
• go
• groovy
• guile
• haskell
• haxe
• java
• julia
• js
• kotlin
• lua
• make
• mal
• ocaml
• matlab
• miniMAL
• nim
• perl
• php
• ps
• python
• r
• racket
• rpython
• ruby
• rust
• scala
• swift
• swift3
• tcl
• vb
• vimscript

Also:

• Update: process/stepA_mal.txt and process/guide.md

[kanaka]

I push several implementations to branch issue_166_string_ops.

[kanaka]

@dubek I've started implementing seq and string? on branch issue_166_string_ops. If you want to help, feel free to send PRs to this branch.

I'll probably do make and postscript next.

[kanaka]

@dubek btw, don't bother waiting for travis. Just send pulls against this branch and I'll merge it as soon as I see it. Any issues caught with travis can be dealt with later before this branch is merged onto the mainline.

I might collapse/rebase all the commits into a single commit before merging to master anyways to reduce churn in the main history.

[dubek]

Add a checkbox for process/stepA_mal.txt and process/guide.md updates.

[dubek]

tcl in #169. I'm working on vimscript and D and go.

[kanaka]

I'll take the "javas": groovy, java, scala.

[dubek]

I'll take the sharps: cs, fsharp, vb

And then crsyal, lua, perl.

[kanaka]

@dubek I discovered a bug in some implementations where (keyword? "") throws an error. I added a test in step9 and I'm just going to use travis to show which others still have the issue: https://travis-ci.org/kanaka/mal/builds/108816302

[dubek]

Thanks @kanaka, I just noticed myself that c-sharp has this bug.

[dubek]

@kanaka - Another thing I noticed (in ocaml, maybe others) is that (symbol 'a) and (keyword :a) don't just return the argument (idempotent), as they should (I believe).