Print a progress bar

Erases the current line! (by outputting '\r') Does not print a newline '\n'. Subsequent invocations will overwrite the previous output.

Remember to set the correct buffering mode for stdout:

import System.IO ( hSetBuffering, BufferMode(NoBuffering), stdout )
hSetBuffering stdout NoBuffering

Renders a progress bar

>>> mkProgressBar (msg "Working") percentage 40 30 100
"Working [=======>.................]  30%"

A label that can be pre- or postfixed to a progress bar.

The empty label.

>>> noLabel 30 100
""

A label consisting of a static string.

>>> msg "foo" 30 100
"foo"

A label which displays the progress as a percentage.

Constant width property: ∀ d t : ℕ. d ≤ t → length (percentage d t) ≡ 4

>>> percentage 30 100
" 30%"

A label which displays the progress as a fraction of the total amount of work.

Equal width property: ∀ d₁ d₂ t : ℕ. d₁ ≤ d₂ ≤ t → length (exact d₁ t) ≡ length (exact d₂ t)

>>> exact 30 100
" 30/100"

Start a thread to automatically display progress. Use incProgress to step the progress bar.

Increment the progress bar. Negative values will reverse the progress. Progress will never be negative and will silently stop taking data when it completes.