How can you create a function that specifies both the return type and the external variables to use?
Are the examples below wrong or is it not supported (yet)?
<?php
$arr = ['test' => 'value'];
function test1() use ($arr) : string { // Line 5
return $arr['test'];
}
function test2() : string use ($arr) {
return $arr['test'];
}
The error is:
Parse error: syntax error, unexpected 'use' (T_USE), expecting '{' in [PATH]\index.php on line 5
You can run the code here.
As answered by Adam Cameron in the comments, the problem is that the use language construct only applies to closures, not to all functions. Thus, using it on normal functions makes no sense and is as such not understood by the parser.
When the function in the example code would have been a closure, everything would have worked.
$arr = ['test' => 'value'];
$fn = function() use ($arr) : string {
return $arr['test'];
};
echo($fn()); // outputs 'value'
You can run the code here.
Note that your first attempt is correct: first the use statement, then the return type declaration. Trying to reverse these two will result in a parse error.
Related
Hello I am trying to find a way to match an overloaded function inside of the verify using withArg
The doc doesnt really point this out
every { getResponse.Ids } returns listOf(121212L)
assert( client.getExtIds(Ids) )
verify {
client.getExtIdsCall().call(
withArg {
assertEquals(GetExtIdsRequest.builder()
.withIds("foo")
.withType("bar")
.build().hashCode(), it.hashCode()
)
}
)
}
Something like above. But unfortunately I cant because the client.getExtIdsCall().call() accepts two different types of objects. One of which has the hashCode I want. So the it can not be referred correctly to call the hashCode function
You can resolve this by explicitly specifying the type parameter of function withArg, e.g. if you want your parameter to be a Long, you can write:
withArg<Long> { ... }
I can call the gist method on the say built-in function:
&say.gist
sub say (| is raw) { #`(Sub|54790064) ... }
Why can't I call gist on while?
&while.gist
===SORRY!=== Error while compiling <unknown file>
Undeclared routine:
while used at line 1
Obviously while isn't a "routine" but say is. But I thought that all of the built-ins in Perl 6 were really functions that we could redefine.
I thought that all of the built-ins in Perl 6 were really functions that we could redefine.
while is not a routine or macro, but part of the syntax, defined in Perl6's grammar.
If you wanted to redefine it, you would have to create your own slang, which currently involves black magic.
For some reason I have yet to figure out, it only works when done in a module (otherwise, %*LANG seems not to be defined).
Let's call the module froop.pm6:
use nqp;
sub EXPORT {
nqp::bindkey(%*LANG, 'MAIN', nqp::atkey(%*LANG, 'MAIN').^mixin(role {
rule statement_control:sym<while> {
[$<sym>=froop{
$/.hash<sym>.^mixin: role {
method Str { 'while' }
}
}|$<sym>=until]<.kok> {}
<xblock>
}
}));
once Map.new
}
This replaces the while keyword (in statement position) with froop, eg
use froop;
my $i = 0;
froop $i < 5 { say $i++ }
I use cucumber and chai-as-promised as assertion library. What is the right way to check the count value. I use equal but it works only after converting string to integer.Is there a way to assert a integer value directly?
this.Then(/^the list should contain "([^"]*)" items$/, function (arg1, callback) {
var count=parseInt(arg1);
expect(element.all(by.repeater('item in list.items')).count()).to.eventually.equal(count).and.notify(callback);
});
If you really wanted to, I believe you could bypass parseInt() by using Chai's satisfy() method and JavaScript coercion, as shown below. However, I personally prefer the method you are currently using as it is easier to understand and coercion can be tricky.
this.Then(/^the list should contain "([^"]*)" items$/, function (arg1, callback) {
expect(element.all(by.repeater('item in list.items')).count()).to.eventually.satisfy(function(count) { return count == arg1 } ).and.notify(callback);
});
I have placed the simple linkedin class on my server and added my api keys etc, however when i call the demo page i get the following error:
Parse error: syntax error, unexpected T_FUNCTION in /home/mycv/public_html/dev/linkedin_3.2.0.class.php on line 259
this is the code for the area around line: 259
if(is_array($http_code_required)) {
array_walk($http_code_required, function($value, $key) {
if(!is_int($value)) {
throw new LinkedInException('LinkedIn->checkResponse(): $http_code_required must be an integer or an array of integer values');
}
line 259: seems to refer to the second line starting with array walk.
Thanks
Anonymous functions only became available in PHP 5.3.0. Line 259 above uses an anonymous function, so that would explain the error if your version pre-dates support.
Just make the anonymous function as a named function and call it in the checkResponse function:
function **innerfunction**($value, $key) {
if(!is_int($value)) {
throw new LinkedInException('LinkedIn->checkResponse(): $http_code_required must be an integer or an array of integer values');
}
}
private function checkResponse($http_code_required, $response) {
// check passed data
if(is_array($http_code_required)) {
array_walk($http_code_required, **innerfunction**($value, $key));
}
}
Newbie Rx question. I want to write a method like the following:
public IObsevable<Unit> Save(object obj)
{
var saveFunc = Observable.FromAsyncPattern(...);
saveFunc(obj).Subscribe(result =>
{
Process(result);
return Observable.Return(new Unit());
});
}
The basic idea is: Save the given object, process the results in my "inner" continuation, then allow the caller's "outer" continuation to execute. In other words, I want to chain two continuations together so that the second one does not execute until the first one finishes.
Unfortunately, the code above does not compile because the inner continuation has to return void rather than an IObservable. Plus, of course, returning an observable Unit out of a lambda is not the same as returning it from the containing function, which is what I really need to do. How can I rewrite this code so that it returns the observable Unit correctly? Thanks.
Simplest solution is to use SelectMany
public IObsevable<Unit> Save(object obj)
{
var saveFunc = Observable.FromAsyncPattern(...);
return saveFunc(obj).SelectMany(result =>
{
Process(result);
return Observable.Return(new Unit());
});
}