regex - grep with variable and string combined -

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• difference between single , double quotes in bash 4 answers

i want able use grep variable , string combined searching.

test="http/[0-9].[0-9]"  grep '$test [0-9][0-9][0-9] ||' some_file 

tried put variable in ${test} did not help.

how can combine grep arguments variable , string?

you have enclose pattern in double quotes enable variable expansion :

test="http/[0-9].[0-9]"  grep "$test [0-9][0-9][0-9] ||" some_file 

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test='expanded' echo '$test' # echo $test echo "$test" # echo expanded