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=Overview=
=Overview=


The <tt>for</tt> built-in command expand ''words'', and execute ''commands'' once for each member in the resultant list, with ''name'' bound to the current member.
The <tt>for</tt> built-in command expand ''words'', and execute ''commands'' once for each member in the resultant list, with ''i'' bound to the current member.


<pre>
<pre>
   for name in words; do commands; done
   for i in words; do commands; done
</pre>
</pre>



Revision as of 23:51, 29 February 2016

External

Internal

Overview

The for built-in command expand words, and execute commands once for each member in the resultant list, with i bound to the current member.

   for i in words; do commands; done


If `in words' is not present, the for command executes the commands once for each positional parameter that is set, as if `in "$@"' had been specified (see Positional Parameters below.)


{{{

   for i in words; do commands; done

}}}

If the keyword "in" is not present, Template:For will iterate through positional parameters.

Alternative form:

{{{

   for (( i=0; i<${#names[@]}; i++ )); do
       local name=${names[${i}]}
       echo "${name}"
   done

}}}

!!!Iterating through $1, $2, $3 ...

{{{

    for i do
        echo ${i}
    done

}}}

!!!Iterating through a space separated list


{{{

   s="a b c"
   for i in ${s}
       do
           echo ${i}
       done

}}}

or

{{{

    s="a b c"
    for i in ${s}; do echo ${i}; done

}}}

Note the use of ";"


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