Where exactly do you have problems with the linked nodes?

It helps us help you better if you provide the code you've already written, together with input data, and also the output it generates and the output you expect.

Thanks for your reply. firstly, I am a beginner. I am trying to write a code to do the following. suppose this is my input text file in the format

abc dsdasd dasgg gfg htrh
sdsjk sdasd ds { abc deef gheweri rew jk \ 
  dfs grg gre ret rtr lm nop qrs\
  erwe erewr gf htrh ksdj \} -fdj lf 
erew fsdfj kgfk -bg1 abc dfsdf -bg2 nop fdsfs
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Now - I wanted to write a PERL code to know if the string 'abc', 'dfsdf' , 'nop' and 'fdsfs' in line #5 exist between '{' and '}'. I am not able to figure out how to write the code to implement this. In case of the text file provided above, the result should be something printed like

'abc' and 'nop' are present above
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In my opinion, the link to Parsing a file with parentheses to build a hash is relatively suitable, as it points to a very similar problem, extracting terms between ( and ) instead of { and }.

Depending on the nature of your data, you might be able to simply extract all pairs of {...} and then check those for your keywords. A very simplicistic parser would be:

my $line= 'abc ... {abc} ... abc';
my @terms= $line =~ /\{(.*?)\}/g;
for my $bracketed (@terms) {
    print "$bracketed matches $1"
        if ($bracketed =~ /(abc|nop)/);
};
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This does not care for nested sets of brackets. For parsing nested sets, see the linked node.