Regexp in a variable Shell

Question

I'm doing some regexp in shell to find coding style error in *.c files. Actually I'm doing something like this:

# Operator <
if [[ "$1" =~ ([^ ]<|<[^ =$]) ]]; then
    warn "$wmsg_space_operator (operator: <)"
fi

But I want to do it like this:

# Operator <
regexpOp=([^ ]<|<[^ =$])
if [[ "$1" =~ $regexpOp ]]; then
    warn "$wmsg_space_operator (operator: <)"
fi

How can I do?

sjsam · Accepted Answer · 2016-08-11 13:35:05Z

1

Put regexpOp in quotes

regexpOp='([^ ]<|<[^ =$])'

and rest is assured

Why?

Your regex string contain spaces and anything after the space will be counted as another command.

answered Aug 11, 2016 at 13:35

sjsam

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Comments

chepner · Accepted Answer · 2016-08-11 13:32:28Z

1

You need to quote the assignment, specifically for the whitespace.

# Operator <
regexpOp="([^ ]<|<[^ =$])"
if [[ "$1" =~ $regexpOp ]]; then
    warn "$wmsg_space_operator (operator: <)"
fi

answered Aug 11, 2016 at 13:32

chepner

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