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Top Forums Shell Programming and Scripting Blog-Thread: Creating a Shell Wrapper and Runtime Modifier (SWARM) Post 303045307 by drl on Monday 16th of March 2020 07:10:46 AM
Old 03-16-2020
Hi.

Perhaps I missed something, but variables are created/set when from a function:
Code:
#!/usr/bin/env bash

# @(#) s1       Demonstrate use of option "-g" in "declare".

LC_ALL=C ; LANG=C ; export LC_ALL LANG
pe() { for _i;do printf "%s" "$_i";done; printf "\n"; }
pl() { pe;pe "-----" ;pe "$*"; }
em() { pe "$*" >&2 ; }
db() { ( printf " db, ";for _i;do printf "%s" "$_i";done;printf "\n" ) >&2 ; }
db() { : ; }
C=$HOME/bin/context && [ -f $C ] && $C

(
        declare -g my_test_a="a test"
        export my_test_b="an exported beer"
)

unset my_test_a my_test_b
pl " Results, not in function:"
echo $my_test_a
echo $my_test_b

f1 ()
{
    declare -g my_test_a="a test"
    export my_test_b="an exported beer"
}

unset my_test_a my_test_b
pl " Results, in function f1:"
f1
echo $my_test_a
echo $my_test_b

exit

producing:
Code:
$ ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 3.16.0-7-amd64, x86_64
Distribution        : Debian 8.11 (jessie) 
bash GNU bash 4.3.30

-----
 Results, not in function:



-----
 Results, in function f1:
a test
an exported beer

Seen in man bash:
Quote:
-g create global variables when used in a shell function; otherwise
ignored
and noted with shellcheck:
Code:
...
In s1 line 21:
echo $my_test_a
     ^-- SC2031: my_test_a was modified in a subshell. That change might be lost. 
...

Apologies if I missed it ... cheers, drl

( currently listening: Bartok: String Quartets, but soon Yes )
This User Gave Thanks to drl For This Post:
 
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Locale::Codes::Script(3)				User Contributed Perl Documentation				  Locale::Codes::Script(3)

NAME
Locale::Codes::Script - standard codes for script identification SYNOPSIS
use Locale::Codes::Script; $script = code2script('phnx'); # 'Phoenician' $code = script2code('Phoenician'); # 'Phnx' $code = script2code('Phoenician', LOCALE_CODE_NUMERIC); # 115 @codes = all_script_codes(); @scripts = all_script_names(); DESCRIPTION
The "Locale::Codes::Script" module provides access to standards codes used for identifying scripts, such as those defined in ISO 15924. Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default ISO 15924 four-letter codes will be used. SUPPORTED CODE SETS
There are several different code sets you can use for identifying scripts. A code set may be specified using either a name, or a constant that is automatically exported by this module. For example, the two are equivalent: $script = code2script('phnx','alpha'); $script = code2script('phnx',LOCALE_SCRIPT_ALPHA); The codesets currently supported are: alpha, LOCALE_SCRIPT_ALPHA This is a set of four-letter (capitalized) codes from ISO 15924 such as 'Phnx' for Phoenician. It also includes additions to this set included in the IANA language registry. The Zxxx, Zyyy, and Zzzz codes are not used. This is the default code set. num, LOCALE_SCRIPT_NUMERIC This is a set of three-digit numeric codes from ISO 15924 such as 115 for Phoenician. ROUTINES
code2script ( CODE [,CODESET] ) script2code ( NAME [,CODESET] ) script_code2code ( CODE ,CODESET ,CODESET2 ) all_script_codes ( [CODESET] ) all_script_names ( [CODESET] ) Locale::Codes::Script::rename_script ( CODE ,NEW_NAME [,CODESET] ) Locale::Codes::Script::add_script ( CODE ,NAME [,CODESET] ) Locale::Codes::Script::delete_script ( CODE [,CODESET] ) Locale::Codes::Script::add_script_alias ( NAME ,NEW_NAME ) Locale::Codes::Script::delete_script_alias ( NAME ) Locale::Codes::Script::rename_script_code ( CODE ,NEW_CODE [,CODESET] ) Locale::Codes::Script::add_script_code_alias ( CODE ,NEW_CODE [,CODESET] ) Locale::Codes::Script::delete_script_code_alias ( CODE [,CODESET] ) These routines are all documented in the Locale::Codes::API man page. SEE ALSO
Locale::Codes The Locale-Codes distribution. Locale::Codes::API The list of functions supported by this module. http://www.unicode.org/iso15924/ Home page for ISO 15924. http://www.iana.org/assignments/language-subtag-registry The IANA language subtag registry. AUTHOR
See Locale::Codes for full author history. Currently maintained by Sullivan Beck (sbeck@cpan.org). COPYRIGHT
Copyright (c) 1997-2001 Canon Research Centre Europe (CRE). Copyright (c) 2001-2010 Neil Bowers Copyright (c) 2010-2013 Sullivan Beck This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.16.3 2013-02-27 Locale::Codes::Script(3)

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