Fish: dictionaries / associative arrays / maps

dict.fish

function dict
    set arg_dict (echo $argv[2] | string replace -ar "[^A-Za-z0-9]+" "_")
    set arg_key (echo $argv[3] | string replace -ar "[^A-Za-z0-9]+" "_")

    switch $argv[1]
    case "set"
        if test (count $argv) -gt 3
            set -g $arg_dict'_'$arg_key $argv[4..-1]
        else
            set -g $arg_dict'_'$arg_key
        end
    case "remove"
        for rawkey in $argv[3..-1]
            set arg_key (echo $rawkey | string replace -ar "[^A-Za-z0-9]+" "_")
            set -e $arg_dict'_'$arg_key
        end
    case "clear"
        for pair in (set)
            set varname (echo $pair | string split " ")[1]
            if test (echo $varname | string sub -l (math (echo $arg_dict | string length) + 1)) = $arg_dict'_'
                set -e $varname
            end
        end

    case "keys"
        for pair in (set)
            set varname (echo $pair | string split " ")[1]
            if test (echo $varname | string sub -l (math (echo $arg_dict | string length) + 1)) = $arg_dict'_'
                set keyname (echo $varname | string sub -s (math (echo $arg_dict | string length) + 2))
                echo $keyname
            end
        end
    case "get"
        if test (eval count '$'$arg_dict'_'$arg_key) -ne 0
            eval printf "'%s\n'" '$'$arg_dict'_'$arg_key
        end
    case "has"
        set -q $arg_dict'_'$arg_key
    case "*"
        echo "Invalid command: $argv[1]" 2>&1
    end
end