Zsh shift selection

Question

How to use shift to select part of the commandline (like in many text editors) ?

Answer 1

One way to do it is to

1. define new widgets that activate marking on shifted motion keys,
2. redefine all action widgets to operate on the region (if there is one), and
3. redefine all the default motion widgets to deactivate marking.

Here's a proof of concept (for xterm), working for:

• Shift-Left and Shift-Right: start selecting to the left/right, respectively,
• Left, Right: cancel selecting and move left/right, respectively,
• Delete: delete selection if there is one, otherwise character under the cursor.

The usual disclaimers apply (there may be other and better ways, your cat may eat your toaster, etc.).

bindkey -e

function zle-line-init {
    marking=0
}
zle -N zle-line-init

function select-char-right {
    if (( $marking != 1 )) 
    then
        marking=1
        zle set-mark-command
    fi
    zle .forward-char
}
zle -N select-char-right

function select-char-left {
    if (( $marking != 1 )) 
    then
        marking=1
        zle set-mark-command
    fi
    zle .backward-char
}
zle -N select-char-left

function forward-char {
    if (( $marking == 1 ))
    then
        marking=0
        NUMERIC=-1 zle set-mark-command
    fi
    zle .forward-char
}
zle -N forward-char

function backward-char {
    if (( $marking == 1 ))
    then
        marking=0
        NUMERIC=-1 zle set-mark-command
    fi
    zle .backward-char
}
zle -N backward-char

function delete-char {
    if (( $marking == 1 ))
    then
        zle kill-region
        marking=0
    else
        zle .delete-char
    fi
}
zle -N delete-char

bindkey '^[[1;2D' select-char-left   # assuming xterm
bindkey '^[[1;2C' select-char-right  # assuming xterm