If I run the following code: 

#!/usr/bin/perl -w
use strict;

my %test_hash = ("foo_bar" => "baz");

my $test = "foo";

my $key = "${test}_bar";

my $var1 = "aaa/$test_hash{$key}";

printf("var1 = $var1\n");

my $var2 = "aaa/$test_hash{${test}_bar}";

printf("var2 = $var1\n");

[download]

I receive the following error: 

> ./braces_inside_braces.pl 
Bareword found where operator expected at ./braces_inside_braces.pl li
+ne 14, near "${test}_bar"
        (Missing operator before _bar?)
syntax error at ./braces_inside_braces.pl line 14, near "${test}_bar"
Execution of ./braces_inside_braces.pl aborted due to compilation erro
+rs.

[download]

The curly braces around "test" are required to separate it from "_bar", which is not part of the variable name, yet they are conflicting with the outer curly braces of test_hash. Is there any way to write that on one line without syntax errors, or do I have to use the method shown in the first case where I use the intermediate variable $key?

In reply to curly braces inside of curly braces by Special_K

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