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Tim van der Lippe
6d109a9d45
This also adds Python-2.0 to the list of accepted licenses. Lastly, it fixes a bug where the package.json files were incorrectly reordered. For the `exports` of a particular package, the order that the entrypoints are defined in is crucial. Therefore, we should not alter the order of entrypoints and instead maintain the originally defined ordering. We can use an `OrderedDict` to ensure that Python always loads the JSON files in the same order. DISABLE_THIRD_PARTY_CHECK=NPM update R=jacktfranklin@chromium.org Bug: none Change-Id: I5a309782de6015edea6ba3b502aa0db1f008d973 Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/2692909 Auto-Submit: Tim van der Lippe <tvanderlippe@chromium.org> Reviewed-by: Jack Franklin <jacktfranklin@chromium.org> Commit-Queue: Tim van der Lippe <tvanderlippe@chromium.org>
once
Only call a function once.
usage
var once = require('once')
function load (file, cb) {
cb = once(cb)
loader.load('file')
loader.once('load', cb)
loader.once('error', cb)
}
Or add to the Function.prototype in a responsible way:
// only has to be done once
require('once').proto()
function load (file, cb) {
cb = cb.once()
loader.load('file')
loader.once('load', cb)
loader.once('error', cb)
}
Ironically, the prototype feature makes this module twice as complicated as necessary.
To check whether you function has been called, use fn.called. Once the
function is called for the first time the return value of the original
function is saved in fn.value and subsequent calls will continue to
return this value.
var once = require('once')
function load (cb) {
cb = once(cb)
var stream = createStream()
stream.once('data', cb)
stream.once('end', function () {
if (!cb.called) cb(new Error('not found'))
})
}
once.strict(func)
Throw an error if the function is called twice.
Some functions are expected to be called only once. Using once for them would
potentially hide logical errors.
In the example below, the greet function has to call the callback only once:
function greet (name, cb) {
// return is missing from the if statement
// when no name is passed, the callback is called twice
if (!name) cb('Hello anonymous')
cb('Hello ' + name)
}
function log (msg) {
console.log(msg)
}
// this will print 'Hello anonymous' but the logical error will be missed
greet(null, once(msg))
// once.strict will print 'Hello anonymous' and throw an error when the callback will be called the second time
greet(null, once.strict(msg))