On 2017-01-13 09:01:32 GMT, Todd Chester wrote:
Hi All,
Advertising
I am trying to understand how to read variables from the
shell's environment. I am reading this:
https://docs.perl6.org/language/variables#Dynamic_variables
<code>
#!/usr/bin/perl6
# print "Display = " + %*ENV{'DISPALY'} + "\n";
print "Perl Version = " + $*PERL + "\n";
</code>
$ ./env.pl6
Cannot resolve caller Numeric(Perl: ); none of these signatures match:
(Mu:U \v: *%_)
in block <unit> at ./env.pl6 line 3
What am I missing? I'd like to get the one I commented
out on line 2 working too. That gives me the following error:
Use of uninitialized value of type Any in numeric context
in block <unit> at ./env.pl6 line 2
Cannot convert string to number: base-10 number must begin with valid
digits or '.' in '⏏Display = ' (indicated by ⏏)
in block <unit> at ./env.pl6 line 2
Many thanks,
-T
On 01/13/2017 01:27 AM, Siavash wrote:
Hi,
`+` is addition operator:
https://docs.perl6.org/routine/$PLUS_SIGN#(Operators)_infix_+
String concatenation operator is `~`:
https://docs.perl6.org/routine/$TILDE#(Operators)_infix_~
So you should write:
print "Perl Version = " ~ $*PERL ~ "\n";
Or use `say` or `put` to add a newline:
say "Perl Version = $*PERL";
So for your commented line, you can write:
say "Display = %*ENV<DISPLAY>"
Thank you!
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