[Q] How to lazy init time a snippet?

[Niklas Adam]

Hi snippet folks!

I would like to pass a number/string to a function called in a snippet. But within the snippet. So to say. Hope this makes sense.

Code is maybe clearer than me trying to explain what I want.

local format = string.format
F = {}

function F.randf_array(num)
    local list = ""
    local randnum = math.random(3,8)
    if num == nil then num = randnum end
    for i=1,num,1 do
        list = list .. tostring(math.random())
        if i < num then list = list .. ", " end
    end
    return format("[%s]", list)
end

snippets = {
    _global = {
           some = [[Some(${1|F.randf_array()}, ${2:inf})]]; -- fine, creating random size of array (3-8 random floats)
           fruit = [[Fruit(${1|F.randf_array(5)}, ${2:inf})]]; -- fine, creating array of size 5 with random floats
           -- here comes the pseudo code
           other = [[Other(${1|F.randf_array(${-1=vim.fn.input("how many random floats would you like? ")})}, ${2:inf})]]; -- not ok, failing
    };
}

I wonder how to do the thing I sketch out in the snippet other ?
And not necessarily with vim.fn.input I would rather just write ${1(require'snippets'.u.lazy_magic):20} .. :)
Something that makes the snippet wait until the value for the randf_array(num) function has been entered.
Preferably with an UX (user experience) similar to if it had been the first $ entry in the snippet (eg. $1)

any help much appreciated.

[Niklas Adam]

Okay so I tried with repeat until and it does work.
However I am being prompted several times to enter my value (number/integer) before returning to the snippet and then being able to expand again. AND then the process starts over. But this time around I am only prompted two times.
The second time I enter a number (this second time of expanding/advancing the snippet) the function actually behaves as expected.
I end up with a list/array of random floats with the size of the number inputted via vim.fn.input.
Any idea why this is?

For testing/reproducing use the floaty ux inserter.

local format = string.format
F = {}

function F.randf_array_query()
    local list = ""
    local n
    repeat
        n = vim.fn.input("how many random floats? ")
        if tonumber(n) == nil then
            print ('enter a number')
        end
        until type(tonumber(n)) == "number"
    -- until tonumber(n) ~= nil
    for i=1,tonumber(n),1 do
        list = list .. tostring(math.random())
        if i < tonumber(n) then list = list .. ", " end
    end
    return format("[%s]", list)
end

snippets = {
    _global = {
        flist = "${1|F.randf_array_query()}";
    };
}

[Niklas Adam]

Interesting enough, If using this as the snippet flist = "${|F.randf_array_query()}";
The input is only prompting three times and then returning the array of floats.

[Niklas Adam]

same "three times"-behavior with a while do loop version.

function F.randf_array_query()
    local list = ""
    local n
    while tonumber(n)==nil do
    n = vim.fn.input("how many random floats? ")
    end
    for i=1,tonumber(n),1 do
        list = list .. tostring(math.random())
        if i < tonumber(n) then list = list .. ", " end
    end
    return format("[%s]", list)
end

[Niklas Adam]

ahhh.. (S.v) .. slowly learning lua here :<)

[Niklas Adam]

yepp

function F.randfs(n)
    local list = ""
    n = tonumber(n) or 0
    if n == 0 then
        return ""
    end
    for i=1,tonumber(n),1 do
        list = list .. tostring(math.random())
        if i < tonumber(n) then list = list .. ", " end
    end
    return format("[%s]", list)
end

snippet: flist = "${1|F.randfs(S.v)}";