perl exact match

Shell Programming and Scripting
1

How to emulate grep -o option in perl.
I mean to print not all line, only the exact match.

echo "2A2 BB" | perl -ne 'print if /2A2/'
2A2 BB

I want to print only 2A2.

2 
echo "2A2 BB" | perl -ne 'print $1 if /(2A2)/'

or

echo "2A2 BB" | perl -ne 'print $1,"\n" if /(2A2)/'

if you want it newline terminated

3

Or:

zsh-4.3.9[sysadmin]% echo 2A2 BB|perl -lne'print/(2A2)/'       
2A2