neyuki 0.4.0

A small Lua-like scripting language implemented in Rust
Documentation 
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-- A bouncing ball that follows clicks. Escape or the close button ends it.

local ui = require("@neyuki/ui")
local math = require("@neyuki/math")

local win = ui.open({ title = "Neyuki UI", width = 640, height = 400 })
local ball = { x = 320, y = 200, vx = 180, vy = 120, r = 24 }
local clicks = 0

ui.run(function(events: {Event}, dt: number)
    for _, event in events do
        if (event.kind == "keydown" and event.key == "escape") then
            win:close()
            return
        elseif (event.kind == "mousedown" and event.button == "left") then
            ball.x, ball.y = event.x, event.y
            clicks += 1
        end
    end

    local w, h = win:size()
    ball.x += ball.vx * dt
    ball.y += ball.vy * dt
    if (ball.x < ball.r or ball.x > w - ball.r) then ball.vx = -ball.vx end
    if (ball.y < ball.r or ball.y > h - ball.r) then ball.vy = -ball.vy end
    ball.x = math.clamp(ball.x, ball.r, w - ball.r)
    ball.y = math.clamp(ball.y, ball.r, h - ball.r)

    win:clear("#1e1e2e")
    win:line(0, h / 2, w, h / 2, "#313244", { width = 2 })
    win:circle(ball.x, ball.y, ball.r + 6, "#89b4fa55")
    win:circle(ball.x, ball.y, ball.r, "#89b4fa")
    win:fillRect(12, 12, 200, 44, "#313244", { radius = 8 })
    win:text(24, 22, "clicks: " .. tostring(clicks), { size = 18, color = "#cdd6f4" })
    win:text(12, h - 28, "click to move the ball, escape to quit", { size = 14, color = "#a6adc8" })
    win:present()
end)