`weekdayRange()`

True on the given weekday or within the weekday range (SUN, MON, ... SAT). Local time unless "GMT" is passed.

weekdayRange(wd1 [, wd2] [, "GMT"])  →  boolean

Time-dependent PACs are hard to test and behave differently per engine; the checker evaluates them at a fixed “now” so results are reproducible.

Example

if (weekdayRange("MON", "FRI")) {
  return "PROXY proxy.corp.example:8080";
}

Engine	Behaviour	Source
chromium	Supports wrap-around ranges such as FRI to MON.	code, verified 2026-10-04 services/proxy_resolver/pac_js_library.h@cb6eb0e7
firefox	Supports wrap-around ranges.	code, verified 2026-10-04 netwerk/base/ascii_pac_utils.js@3f73c528
pacparser	No wrap-around: a range like FRI to MON never matches.	code, verified 2026-10-04 src/pac_utils.h@v1.5.3

Derived from each engine's vendored helper library plus its native bindings (see engines).
Function	chromium <=51	chromium >=52	firefox all	pacparser <=1.4.6	pacparser 1.5.0	pacparser >=1.5.1	reference all
`weekdayRange`	yes	yes	yes	yes	yes	yes	yes