Insert item into zsh array

Question

Let's say I have an array defined as such:

  typeset -g POWERLEVEL9K_LEFT_PROMPT_ELEMENTS=(
    os_icon
    dir
    vcs
    newline
    prompt_char
  )

Now I want to insert an item my_item into the array after vcs. I don't know what index vcs is at, all I know is that I want to insert it right after vcs

I tried

POWERLEVEL9K_LEFT_PROMPT_ELEMENTS=(${POWERLEVEL9K_LEFT_PROMPT_ELEMENTS:s/vcs/vcs my_item})

But for some reason that does not work. The followed does work for substitution:

POWERLEVEL9K_LEFT_PROMPT_ELEMENTS=(${POWERLEVEL9K_LEFT_PROMPT_ELEMENTS:s/vcs/my_item})

But of course will remove vcs.... I'm obviously not getting the space correct, but can't seem to get it right.

Answer 1

Adding an element of an array in zsh via a somewhat different subscript then that given in Tom Regner's answer. Zsh almost always has more then one way to do the same thing.

Also using indexing to locate the element that the new element will be inserted after. 1 is then added to the index. Note the ,0 in the subscript.

POWERLEVEL9K_LEFT_PROMPT_ELEMENTS[((${POWERLEVEL9K_LEFT_PROMPT_ELEMENTS[(i)vcs]}+1)),0]=my_item

You may also find the following subscript useful.

To add an element before the first element of an array:

POWERLEVEL9K_LEFT_PROMPT_ELEMENTS[1,0]=new_first_element

This effectively shifts all existing elements to the right.