How to convert between the unicode forms: string, name, number - bash

Question

I have been lately using unicode more often and wondered if there is a command line tool to convert unicode between its forms.
Would be nice to be able to say:
uni_convert "☃" --string
And know that the string is defined in unicode as a "SNOWMAN".

Answer 1

Perl's Unicode-Tussle distribution comes with the useful uniprops.
$ uniprops '☃'
U+2603 ‹☃› \N{SNOWMAN}
...
$ uniprops 'U+2603'
U+2603 ‹☃› \N{SNOWMAN}
...
$ uniprops 'SNOWMAN'
U+2603 ‹☃› \N{SNOWMAN}
...
If you're writing code, you'll want charnames.
Want
Have
Code
$code
$char
ord($char)
$code
$name
charnames::vianame($name)
$char
$code
chr($code)
$char
$name
chr(charnames::vianame($name))
$name
$code
charnames::viacode($code)
$name
$char
charnames::viacode(ord($char))
vianame accepts official aliases (e.g. LF for LINEFEED). You'll need to parse U+ notation yourself if wish to accept it. ($code = hex(s/^U\+//r);)
Example:
use strict;
use warnings;
use feature qw( say );
use experimental qw( regex_sets ); # Safe. Optional since 5.36.
use utf8; # Source encoded using UTF-8.
use open ":std", ":encoding(UTF-8)"; # Terminal provides/expects UTF-8.
use charnames qw( :full );
use Encode qw( decode_utf8 );
#ARGV == 1
or die("usage\n");
my $s = decode_utf8($ARGV[0]);
for my $cp ( unpack "W*", $s ) {
my $ch = chr($cp);
if ( $ch =~ /(?[ \p{Print} - \p{Mark} ])/ ) { # Not sure if good enough.
printf "‹%s› ", $ch;
} else {
print "--- ";
}
printf "U+%X ", $cp;
say charnames::viacode($cp);
}
$ uni_id ☃
‹☃› U+2603 SNOWMAN
$ uni_id çà
‹ç› U+E7 LATIN SMALL LETTER C WITH CEDILLA
‹à› U+E0 LATIN SMALL LETTER A WITH GRAVE
Other resources:
Unicode::UCD
Provides accsess at the information found in the Unicode Character Database.
The Unicode Standard is more than characters and properties.
perluniprops
unichars from Unicode-Tussle (e.g. unichars '\p{Hiragana}')

Answer 2

Here is an awk to do that.
Download this file from unicode.org that provides the latest names.
Then:
q=$(printf '%x\n' \'☃)
awk '/^[[:xdigit:]]+/{
str=$0
sub(/^[[:xdigit:]]+[[:blank:]]+/,"",str)
names[$1]=str
}
END{ print names[q] }
' q="$q" names.txt
Prints:
SNOWMAN
If you want to go the other way:
cp=$(awk '/^[[:xdigit:]]+/{
str=$0
sub(/^[[:xdigit:]]+[[:blank:]]+/,"",str)
other_names[str]=$1
}
END{ print other_names[q] }
' q="SNOWMAN" names.txt)
echo -e "\u${cp}"
Prints:
☃
If you have GNU awk you can easily convert the hex index into decimal and can print from within. This allows a single source file to be used and go one way or the other by defining q or r:
gawk '/^[[:xdigit:]]+/{
str=$0
sub(/^[[:xdigit:]]+[[:blank:]]+/,"",str)
names[$1]=str
other_names[str]=$1
}
END{ print q ? names[q] : sprintf("%c", strtonum("0x" other_names[r])) }
' r='SNOWMAN' names.txt
☃
gawk '/^[[:xdigit:]]+/{
str=$0
sub(/^[[:xdigit:]]+[[:blank:]]+/,"",str)
names[$1]=str
other_names[str]=$1
}
END{ print q ? names[q] : sprintf("%c", strtonum("0x" other_names[r])) }
' q=$(printf '%x\n' \'☃) names.txt
SNOWMAN

Answer 3

I separated the code into a file and created a repo:
https://github.com/poti1/uni_convert