┌──────────────────────────────────┐
│  progress — bars and spinners    │
└──────────────────────────────────┘

Determinate bars in ten styles, tick spinners, readouts, one-call status lines. Every renderer is pure: same inputs, same string.

Install

zz add progress

Bars

import progress.bar

bar.blocks(0.625, 8)    // [█████░░░]
bar.ascii(0.625, 8)     // [#####---]
bar.arrow(0.625, 8)     // [=====>..]
bar.gradient(0.625, 8)  // truecolor green→yellow→red

Style	Const	Notes
blocks	STYLE_BLOCKS	█/░
partial	STYLE_PARTIAL	1/8-cell ▏…█ precision
shaded	STYLE_SHADED	quartile ░▒▓█
ascii	STYLE_ASCII	#/-, log-safe
arrow	STYLE_ARROW	= fill chasing >
dots	STYLE_DOTS	●/○
thin	STYLE_LINE	─/· (const is STYLE_LINE)
circle	STYLE_CIRCLE	quarter fills ◔◑◒◓
squares	STYLE_SQUARES	■/□ download-style
spectrum	STYLE_SPECTRUM	rainbow lerp
marquee	(tick, w, size)	bouncing block for unknown totals
stages	(done, total)	●●●○○ 3/5 pipeline steps
transfer	(label, done, total, w)	`dl [■■□□] 1
mini	(frac, w)	▰/▱ minimalist
arrow_at	(frac, w, tick)	arrow with throbbing head
gradient	STYLE_GRADIENT	truecolor fill + dim track
vbar	—	vertical column, returns row strings

All clamp frac to [0, 1]; w <= 0 yields "[]".

Readouts

bar.pct(0.625)          // 62.5%
bar.count(30, 48)       // 30/48
bar.rate(30, 2000)      // 15.0/s  (--/s when clockless)
bar.eta(30, 48, 2000)   // 00:01   (--:-- when stalled)
bar.clock(61000)        // 01:01

One call

import progress.bar as bar

o := bar.defaults()
o.label = "dl"
o.count = 1
println(bar.line(o, 30, 48, 2000))
// dl [████████████░░░░░░░░] 62.5% 30/48

Opts flags pick the readouts; style picks the renderer. fg/bg take 256-color codes (-1 = plain) to color the bar in one flag — renderers themselves stay monochrome so they work in logs and pipes. (Import with an alias: cross-module struct types need it.)

Spinners

import progress.spin

spin.at(1, tick)             // frame for an ever-increasing tick
spin.frames(2)               // ["|", "/", "-", "\\"]
spin.run("working", 1, 6, 120)  // label + 6 ticks, returns ticks

Styles: dots, line, arc, bounce, clock, moon, earth, box, arrows, toggle, grow, burger, crescent, orbit, pulse, pie, diamond, sweep, star (consts SPIN_DOTS…SPIN_STAR). Crescent/earth like emoji fonts; everything else is DejaVu-safe.

Try them all live (~3 s): d_zz run examples/gallery.zz spin.

Live loop recipe

t := time.now_ms()
i := 0
while i < total {
    print("\r" + bar.line(o, i, total, time.now_ms() - t))
    // ... work ...
    i = i + 1
}
println("")

Needs import std.time. One print per tick plus a final newline.

Docs

• docs/api.md — every function and signature

MIT — see LICENSE.