OR two values in shell script?

Question

I have a variable that may or may not be empty. If it's not empty, I want that value. If it is empty, I want the value of some other command. Example:

my_function ()
{
    name_override="$1"
    user_name=${name_override} || $(git config "user.name")
}

I'm not sure if the code above will work. But basically I want to run git config and store that result in user_name if the name_override variable is unset (and thus $1 would not have been provided).

How can I do this correctly?

possible duplicate of [Assigning default values to shell variables with a single command in bash](http://stackoverflow.com/questions/2013547/assigning-default-values-to-shell-variables-with-a-single-command-in-bash) — Tom Fenech, Sep 21 '14 at 16:54
@TomFenech Thanks that does answer my question. I did search prior to posting but I did not find that. — void.pointer, Sep 21 '14 at 16:56

score 1 · Accepted Answer · answered Sep 21 '14 at 16:50

1

The bash idiom for accomplishing this is

user_name=${1:-$(git config "user.name")}

where :- says to use the value of $1 if it is set and non-null, else use the following string.

answered Sep 21 '14 at 16:50

chepner

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OR two values in shell script?

1 Answers1