[SOLVED] Bash Script - Map ASCII Characters to Corresponding Unicode Characters in Defined Strings

Issue

I'm trying to map a fixed set of ASCII characters to a fixed set of Unicode characters. I.e., for each digit 0-9, I want to get the circled digit equivalent.

mapFrom="0123456789"
mapTo="🄋➀➁➂➃➄➅➆➇➈"

today=20221018

#convert to "➁🄋➁➁➀🄋➀➇"
todayWithCircles=$(do_something_here) # <-- what's the "something"?

echo $todayWithCircles
# output: ➁🄋➁➁➀🄋➀➇

Given two fixed strings of equal length, what is the easiest way to map them-- based on their position in the string-- as described?

Solution

A quick and dirty approach using perl to do the translating:

#!/usr/bin/env bash

mapFrom="0123456789"
mapTo="🄋➀➁➂➃➄➅➆➇➈"
today=20221018

perl -CSD -Mutf8 -pe "tr/$mapFrom/$mapTo/" <<<"$today"

outputs

➁🄋➁➁➀🄋➀➇

(Assuming the script is encoded in UTF-8, of course. -CSD tells perl to use UTF-8 encoding for standard input, output, and other opened files, -Mutf8 tells it that the script itself (The argument to -e) is encoded in UTF-8.)

If you have GNU sed available, you can use it instead:

sed "y/$mapFrom/$mapTo/" <<<"$today"

(See this unix stackexchange Q&A for why tr isn't suitable)

Answered By - Shawn

Answer Checked By - Mildred Charles (WPSolving Admin)