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Iterating over pairs of command line arguments

I have over 400 coordinates that I want to pass as an argument to a string, but I don't know how to pass the first argument as "lat" and the second argument as "lng", etc. for the rest.

Let's say I went through this

./test 1 2 3 4

I want my conclusion to be

coordinate: {lat: 1, lng: 2}
coordinate: {lat: 3, lng: 4}

This is what I have so far, but obviously it is not.

for i in $@
do

    echo "coordinate: {lat: $i, lng: $i}"

done
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3 answers 


#!/usr/bin/env bash
while (( "$#" >= 2 )); do
  echo "coordinate: {lat: $1, lng: $2}"
  shift 2
done


Note that shift; shift

in many circles it is preferable shift 2

because it works even where there is only one argument left; shift 2

is safe above only because we are comparing $#

so that two or more arguments always exist.

+4


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You don't need a loop:

printf "coordinate: {lat: %s, lng: %s}\n" "$@"


And rename your script before putting your path (something like / usr / local / bin), as test

is a built-in function.

+3


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You can use shift

(but don't do it like this: see comments below):

while [ -n "$1" ]
do
    echo "{coordinate: {lat: $1, lng $2}"
    shift 2
done
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