CIAvash

I was looking for a way to transliterate(translate) English numbers to Persian numbers in Go. Such functionality is usually found in programming languages, but I wasn't expecting too much from Go.

It's very easy to do in Raku:

say 567.trans: '0'..'9' => '۰'..'۹'
=output ۵۶۷␤

say TR/0..9/۰..۹/ given 567
=output ۵۶۷␤

For Go I found xstrings module which has a Translate function. But the solution I came up with was using NewReplacer function from Go's internal strings module:

package main

import (
	"fmt"
	"strings"
)

func main() {
	fmt.Println(strings.NewReplacer(`0`, `۰`, `1`, `۱`, `2`, `۲`, `3`, `۳`, `4`, `۴`, `5`, `۵`, `6`, `۶`, `7`, `۷`, `8`, `۸`, `9`, `۹`).Replace(`567`))
}

Go playground link

After I finished watching Daniel Sockwell's FOSDEM 2022 Raku presentation, I thought this is a good opportunity to play with Raku's slangs, something I hadn't done before.

What is Daniel's talk(and upcoming module) and my module going to solve?

• Write less but more readable test code
• Get a useful test description and failure message

If you use cmp-ok, you get a good error message; but without a test description it's sometimes hard to understand. Also cmp-ok and other test functions(most of them, use-ok being an exception for example) do not output anything on a successful test, unless you provide the description yourself. I personally think that test sub routines should generate a description if one is not provided. But of course that cannot be done with simple functions. Maybe the Test module needs to be rethought in the future?

When I created my Raku programming language website with Hugo static site generator, I had to manually create the syntax highlighted html files for code examples shown in the front page, because Hugo used Chroma(written in Go and uses a mostly similar API to Pygments) for syntax highlighting which didn't support Raku. So I opened an issue on Chroma, the discussion showed that you cannot just convert the Raku lexer from Pygments to Chroma; You would need to create some functions manually, and Chroma needed a new Emitter interface which would take the LexerState as an argument, because Raku has some complex syntax; the Raku lexer in Pygments had functions for finding closing brackets matching the opening brackets, and for regex nesting in tokens, regexes and rules. In the end I realized functions for token nesting were unnecessary.