warning

Warnings and hints

warp tells you about code that runs but may not do what you meant. Every such message has a level:

level	example
hint	one plus two prefers 1 + 2; 2 ** 3 prefers 2 ^ 3
weak	@parallel square xs runs in sequence
normal	most warnings, and your own warn "careful"
severe	if key == ESCAPEE compares with a key name that names nothing

The program still runs; the message names the line and, where it can, a fix:

warn "careful"; 1

warning: careful

Weak and severe warnings say their level: warning (weak): …, warning (severe): …. Errors are not warnings: they stop the program (see Error).

Showing fewer

Everything from hints up is shown by default. Raise the threshold on the command line:

warp --no-hints app.warp          # from weak up (or WARP_HINTS=0)
warp --warnings=severe app.warp   # only severe ones; hint, weak, normal, severe

The playground has the same choice as its "show … and up" select.

Strict

use strict in the program, or warp --strict, makes warnings from normal up errors:

use strict
"a" + warning("careful")   // Error("careful")

--strict=<level> fails from that level instead: --strict=severe fails only on severe warnings, --strict=weak on weak ones too. Hints never fail. See also strict and Footguns.