csh echo foreach 循环索引

Question

Hi I'm new to shell scripting in csh and I need help with an annoying problem. Take the code below:

   set s = ("one" "two" "three" "four")
   foreach i (${s})
      echo $i"-" [what do I put here to get the index?]
   end

This yields the output

  one-
  two-
  three-
  four-

However, I would also like to print out the loop counter index too, so:

  one-1
  two-2
  three-3
  four-4

Sorry if this question is really basic but I don't have much experience in shell scripting (let alone csh) and forums and other stack-overflow posts didn't help much.

Answer 1

You'll need to use a separate variable which you manually increment:

set s = ("one" "two" "three" "four")
set i = 0
foreach v ( $s )
    echo "$v - $i"
    @ i = $i + 1

    # Also works
    #@ i++
end

You can do arithmetic by using the special @ command (the space between @ and i is mandatory since this is a command, and not "syntax", you can actually use any expression here, not just arithmetic).

Since i (for "iteration") is sort-of the standard name for this, I renamed your $i to $v for "value".

As a final note, you probably don't want to use csh for scripting if it can be avoided. It has many problems and limitations.