シェルスクリプトでスクリプトの引数をループする方法

#!/usr/bin/env bash

for arg in "$@";do
  echo "$arg"
done

$ ./arg1.sh a b c
a
b
c

#!/usr/bin/env bash

function func {
  for arg in "$@";do
    echo "$arg"
  done
}

func a b c

$ ./arg2.sh
a
b
c

#!/usr/bin/env bash

for arg do
  echo "$arg"
done

The for Loop
The for loop shall execute a sequence of commands for each member in a list of items. The for loop requires that the reserved words do and done be used to delimit the sequence of commands.

The format for the for loop is as follows:

for name [ in [word ... ]]
do
    compound-list
done

First, the list of words following in shall be expanded to generate a list of items. Then, the variable name shall be set to each item, in turn, and the compound-list executed each time. If no items result from the expansion, the compound-list shall not be executed. Omitting:

in word...
shall be equivalent to:

in "$@"

#!/usr/bin/env bash

for arg
do
  echo "$arg"
done

for name [ [ in [ word ... ] ] ; ] do list ; done
   The  list  of  words following in is expanded, generating a list of items.  The variable name is set to
   each element of this list in turn, and list is executed each time.  If the in word is omitted, the  for
   command  executes  list  once  for  each  positional parameter that is set (see PARAMETERS below).  The
   return status is the exit status of the last command that executes.  If the expansion of the items fol‐
   lowing in results in an empty list, no commands are executed, and the return status is 0.

#!/usr/bin/env bash

for arg; { echo "$arg"; }

#!/usr/bin/env zsh

for arg { echo "$arg"; }

#!/usr/bin/env bash

for arg
{ echo "$arg"; }