Re: [PHP-DEV] [RFC]

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  108530
February 13, 2020 07:33 rowan.collins@gmail.com (Rowan Tommins)
On 13 February 2020 03:33:32 GMT+00:00, Mike Schinkel <mike@newclarity.net> wrote:
>> On Feb 12, 2020, at 5:47 PM, Rowan Tommins collins@gmail.com> >wrote: >> >> On 12/02/2020 03:58, Mike Schinkel wrote: >>> Returning a_closure_ instead of a string would be providing a >feature we_already_ have instead of one we do_not_ have. >> >> >> Not really, because you still need a way to get the fully-qualified >name of the function. This is not valid: >> >> namespace MyVendor\Something\Foo; >> function bar() {} >> >> \Closure::fromCallable('bar'); # Error: tries to resolve function >'\bar' >> > >Why would ::function return a short name instead of the fully-qualified >name?
I never said it would; the intent of this example was to show what is possible in current PHP, in response to your comment about returning a closure being "a feature we already have". The key new feature being proposed is a way to resolve an unqualified function name based on current namespace and imports, without calling the function. The open question is whether the result of that should be expressed as a string or as a Closure object, but in current PHP the feature doesn't exist at all. Regards, -- Rowan Tommins [IMSoP]
  108544
February 13, 2020 17:06 mike@newclarity.net (Mike Schinkel)
> On Feb 13, 2020, at 2:33 AM, Rowan Tommins collins@gmail.com> wrote: > > On 13 February 2020 03:33:32 GMT+00:00, Mike Schinkel <mike@newclarity.net> wrote: >>> On Feb 12, 2020, at 5:47 PM, Rowan Tommins collins@gmail.com> >> wrote: >>> >>> On 12/02/2020 03:58, Mike Schinkel wrote: >>>> Returning a_closure_ instead of a string would be providing a >> feature we_already_ have instead of one we do_not_ have. >>> >>> >>> Not really, because you still need a way to get the fully-qualified >> name of the function. This is not valid: >>> >>> namespace MyVendor\Something\Foo; >>> function bar() {} >>> >>> \Closure::fromCallable('bar'); # Error: tries to resolve function >> '\bar' >>> >> >> Why would ::function return a short name instead of the fully-qualified >> name? > > > I never said it would; the intent of this example was to show what is possible in current PHP, in response to your comment about returning a closure being "a feature we already have". > The key new feature being proposed is a way to resolve an unqualified function name based on current namespace and imports, without calling the function. The open question is whether the result of that should be expressed as a string or as a Closure object, but in current PHP the feature doesn't exist at all.
Let me clarify for you what I was trying to say. 1. IF foo::function returns a name string THEN using Closure::fromCallable( foo::function ) can provide a closure. 2. IF foo::function returns a closure THEN how to we get the name string? Hence we already have a way to get the closure _if_ ::function returns a name string, but we would *not* have a way to get the name string if ::function returns a closure. IOW, we can already derive a closure if we have a name, but we cannot derive a name if we have a closure. I hope this clarifies what I was trying to say when I said "we already have it." -Mike
  108546
February 13, 2020 17:26 rowan.collins@gmail.com (Rowan Tommins)
On Thu, 13 Feb 2020 at 17:06, Mike Schinkel <mike@newclarity.net> wrote:

> 1. IF foo::function returns a name string THEN using > Closure::fromCallable( foo::function ) can provide a closure. > > 2. IF foo::function returns a closure THEN how to we get the name string? >
Right, I'm with you now. However, I think the answer people are suggesting to "how do we get the name string?" is "why do we need to?" Or as Chase Peeler more eloquently put it:
> Can anyone think of a use-case where you would want a string name of a > function and a callable would not be acceptable, besides possibly debugging
> code that said 'echo "I'm calling ".myfunction::function;'? Everything that
> I can think of that accepts a function name, also accepts a callable (e.g.
> array_map), but I could be forgetting something.
There's a Venn diagram, essentially, of: a) use cases where a Closure would be useful, but a string wouldn't b) use cases where a string would be useful, but a Closure wouldn't c) use cases where either a string or a Closure would be useful If (and it's a genuine open question) all the use cases fall into categories (a) and (c), we can make the syntax for closures simpler by skipping the "get name" step and making foo::fn return a closure straight away. So the question is, are there use cases that fall into category (b)? Regards, -- Rowan Tommins [IMSoP]
  108547
February 13, 2020 18:19 mike@newclarity.net (Mike Schinkel)
> On Feb 13, 2020, at 12:26 PM, Rowan Tommins collins@gmail.com> wrote: > Right, I'm with you now. However, I think the answer people are suggesting > to "how do we get the name string?" is "why do we need to?"
1. Say I want to provide users with the ability to build queries and use functions where I want to provide the names of the functions to the users: $qt = QueryTool(); $qt->addFunction(substr::function); $qt->addFunction(add_product::function); $qt->showUI(); 2. Say I want to serialize any configuration that uses functions. You can't serialize closures but you can serialize function names to a database or JSON. 3. You cannot use a closure as an array index so if you want to use the function name as an array key to associate additional information to the use with the function, such as: $qt = QueryTool(); $qt->addFunction(substr::function, array( new FuncParam( 'string', 'string' ), new FuncParam( 'int', 'start', QueryTool::Optional ), new FuncParam( 'int', 'length', QueryTool::Optional ) )); $qt->addFunction(add_product::function, array( new FuncParam( 'string', 'product_id' ), new FuncParam( 'float', 'price' ) )); 4. Being able to compose quality error and warning message that include function names.
> Or as Chase Peeler more eloquently put it: > >> Can anyone think of a use-case where you would want a string name of a >> function and a callable would not be acceptable, besides possibly debugging >> code that said 'echo "I'm calling ".myfunction::function;'? Everything that >> I can think of that accepts a function name, also accepts a callable (e.g. >> array_map), but I could be forgetting something.
Eloquently maybe, but of limited vision.
> There's a Venn diagram, essentially, of: > a) use cases where a Closure would be useful, but a string wouldn't > b) use cases where a string would be useful, but a Closure wouldn't > c) use cases where either a string or a Closure would be useful > > If (and it's a genuine open question) all the use cases fall into > categories (a) and (c), we can make the syntax for closures simpler by > skipping the "get name" step and making foo::fn return a closure straight > away. > > So the question is, are there use cases that fall into category (b)?
Yes. Definitely. But since I seem to be in the minority of caring about the name, let me propose the following which was influenced by Larry Garfield's most recent post. Since it seems that people want the convenience of a short notation to get a closure, how about this: function foo{} foo::function — Returns name of function foo::fn — Returns closure for function Since using `fn` creates anonymous function closures it kinda makes sense that `::fn` would return a closure. -Mike
  108549
February 13, 2020 18:48 larry@garfieldtech.com ("Larry Garfield")
On Thu, Feb 13, 2020, at 12:19 PM, Mike Schinkel wrote:
> > On Feb 13, 2020, at 12:26 PM, Rowan Tommins collins@gmail.com> wrote: > > Right, I'm with you now. However, I think the answer people are suggesting > > to "how do we get the name string?" is "why do we need to?" > > 1. Say I want to provide users with the ability to build queries and > use functions where I want to provide the names of the functions to the > users: > > $qt = QueryTool(); > $qt->addFunction(substr::function); > $qt->addFunction(add_product::function); > $qt->showUI(); > > 2. Say I want to serialize any configuration that uses functions. You > can't serialize closures but you can serialize function names to a > database or JSON. > > 3. You cannot use a closure as an array index so if you want to use the > function name as an array key to associate additional information to > the use with the function, such as: > > $qt = QueryTool(); > $qt->addFunction(substr::function, array( > new FuncParam( 'string', 'string' ), > new FuncParam( 'int', 'start', QueryTool::Optional ), > new FuncParam( 'int', 'length', QueryTool::Optional ) > )); > $qt->addFunction(add_product::function, array( > new FuncParam( 'string', 'product_id' ), > new FuncParam( 'float', 'price' ) > ));
Those are valid examples. I suppose along similar lines would be tooling that uses a builder to generate compiled code. (Eg, if $qt were used to then generate an optimized function in a class on disk.) Flipside: In those cases we really should standardize static methods better than with arrays, yet none of these address (nor can they) instance methods.
> 4. Being able to compose quality error and warning message that include > function names. > > > Or as Chase Peeler more eloquently put it: > > > >> Can anyone think of a use-case where you would want a string name of a > >> function and a callable would not be acceptable, besides possibly debugging > >> code that said 'echo "I'm calling ".myfunction::function;'? Everything that > >> I can think of that accepts a function name, also accepts a callable (e.g. > >> array_map), but I could be forgetting something. > > Eloquently maybe, but of limited vision. > > > > There's a Venn diagram, essentially, of: > > a) use cases where a Closure would be useful, but a string wouldn't > > b) use cases where a string would be useful, but a Closure wouldn't > > c) use cases where either a string or a Closure would be useful > > > > If (and it's a genuine open question) all the use cases fall into > > categories (a) and (c), we can make the syntax for closures simpler by > > skipping the "get name" step and making foo::fn return a closure straight > > away. > > > > So the question is, are there use cases that fall into category (b)? > > Yes. Definitely.
I agree, the above examples demonstrate valid use cases for (b).
> But since I seem to be in the minority of caring about the name, let me > propose the following which was influenced by Larry Garfield's most > recent post. Since it seems that people want the convenience of a > short notation to get a closure, how about this: > > function foo{} > > foo::function — Returns name of function > foo::fn — Returns closure for function > > Since using `fn` creates anonymous function closures it kinda makes > sense that `::fn` would return a closure. > > -Mike
thinking-face-emoji.gif. I could be convinced of that. It seems like "both" is a possible solution, but my concern would be someone using one of them in a case where either works, inadvertently, when the callee is expecting just one. Eg, getting into the habit of using foo::fn, and then using it on a builder routine that chokes "later" when it tries to serialize something. --Larry Garfield
  108550
February 13, 2020 20:12 mike@newclarity.net (Mike Schinkel)
> On Feb 13, 2020, at 1:48 PM, Larry Garfield <larry@garfieldtech.com> wrote: >> But since I seem to be in the minority of caring about the name, let me >> propose the following which was influenced by Larry Garfield's most >> recent post. Since it seems that people want the convenience of a >> short notation to get a closure, how about this: >> >> function foo{} >> >> foo::function — Returns name of function >> foo::fn — Returns closure for function >> >> Since using `fn` creates anonymous function closures it kinda makes >> sense that `::fn` would return a closure. >> >> -Mike > > thinking-face-emoji.gif. I could be convinced of that. It seems like "both" is a possible solution, but my concern would be someone using one of them in a case where either works, inadvertently, when the callee is expecting just one. Eg, getting into the habit of using foo::fn, and then using it on a builder routine that chokes "later" when it tries to serialize something.
True. But it would be a really high bar to say we can only add new features if we can completely protect the developer from themselves. At some point we have to assume programmers are adults, or at least can take responsibility for learning how the language works. -Mike P.S. OTOH, if the routine that requires ::function and not ::fn were to type hint the parameter, it would choke with an applicable error message.
  108552
February 13, 2020 21:55 larry@garfieldtech.com ("Larry Garfield")
On Thu, Feb 13, 2020, at 2:12 PM, Mike Schinkel wrote:
> > On Feb 13, 2020, at 1:48 PM, Larry Garfield <larry@garfieldtech.com> wrote: > >> But since I seem to be in the minority of caring about the name, let me > >> propose the following which was influenced by Larry Garfield's most > >> recent post. Since it seems that people want the convenience of a > >> short notation to get a closure, how about this: > >> > >> function foo{} > >> > >> foo::function — Returns name of function > >> foo::fn — Returns closure for function > >> > >> Since using `fn` creates anonymous function closures it kinda makes > >> sense that `::fn` would return a closure. > >> > >> -Mike > > > > thinking-face-emoji.gif. I could be convinced of that. It seems like "both" is a possible solution, but my concern would be someone using one of them in a case where either works, inadvertently, when the callee is expecting just one. Eg, getting into the habit of using foo::fn, and then using it on a builder routine that chokes "later" when it tries to serialize something. > > True. > > But it would be a really high bar to say we can only add new features > if we can completely protect the developer from themselves. At some > point we have to assume programmers are adults, or at least can take > responsibility for learning how the language works.
Strawman argument. Nothing can "completely" protect developers from themselves; not even Rust. :-) But features should still be designed in such a way as to be hard to screw up. Not impossible, hard. The question I pose is whether "both" would be "hard enough" to get wrong that it's not going to cause more confusion than it solves. I don't know the answer to that question. --Larry Garfield
  108553
February 13, 2020 22:26 d.h.j.takken@freedom.nl (Dik Takken)
On 13-02-2020 19:19, Mike Schinkel wrote:
> But since I seem to be in the minority of caring about the name, let me propose the following which was influenced by Larry Garfield's most recent post. Since it seems that people want the convenience of a short notation to get a closure, how about this: > > function foo{} > > foo::function — Returns name of function > foo::fn — Returns closure for function > > Since using `fn` creates anonymous function closures it kinda makes sense that `::fn` would return a closure.
That is somewhat confusing in my opinion, the two class constants are too similar. I would rather prefer: foo::function — Returns name of function foo::closure — Returns closure for function Regards, Dik Takken
  108557
February 14, 2020 00:31 mike@newclarity.net (Mike Schinkel)
> On Feb 13, 2020, at 5:26 PM, Dik Takken takken@freedom.nl> wrote: > > On 13-02-2020 19:19, Mike Schinkel wrote: >> function foo{} >> >> foo::function — Returns name of function >> foo::fn — Returns closure for function >> >> Since using `fn` creates anonymous function closures it kinda makes sense that `::fn` would return a closure. > > That is somewhat confusing in my opinion, the two class constants are > too similar. I would rather prefer: > > foo::function — Returns name of function > foo::closure — Returns closure for function > > Regards, > Dik Takken
I actually prefer foo::closure over foo::fn though either would be fine with me, especially if it means getting the feature vs. not getting the feature. The reason I proposed ::fn was because I trying to suggest something that I though Larry Garfield would appreciate given his recent comment[1] in response to you where he said: "Analysis: I stand by my earlier statement that ::function is just too damned long for this funtionality. Not when already reserved shorter options exist. ::fn" -Mike [1] https://externals.io/message/108459#108542
  108555
February 14, 2020 00:24 rowan.collins@gmail.com (Rowan Tommins)
On 13 February 2020 18:19:08 GMT+00:00, Mike Schinkel <mike@newclarity.net> wrote:
>Eloquently maybe, but of limited vision.
I think that's a rather negative way of putting it; there was a request for use cases, and you have supplied some, so thank you. :) An idea I had earlier which might solve some of them is if what was returned was not a normal Closure instance, but a new class like FunctionReference. It could then "remember" the name of the function wrapped, and implement __toString, Serializable, etc. It could inherit from Closure, so instanceof checks would work, and bindTo would return a normal Closure. I'm sure there's downsides I haven't thought of yet, but I thought I'd throw the idea into the mix. A possible future direction would then be to have ::class return some kind of ClassRef object, with the obvious downside that it would no longer pass string type hints without casting. I'm also not sure what the object would do, other than feel nicer from a type system point of view. Regards, -- Rowan Tommins [IMSoP]
  108558
February 14, 2020 00:39 mike@newclarity.net (Mike Schinkel)
> On Feb 13, 2020, at 7:24 PM, Rowan Tommins collins@gmail.com> wrote: > > An idea I had earlier which might solve some of them is if what was returned was not a normal Closure instance, but a new class like FunctionReference. It could then "remember" the name of the function wrapped, and implement __toString, Serializable, etc. It could inherit from Closure, so instanceof checks would work, and bindTo would return a normal Closure. I'm sure there's downsides I haven't thought of yet, but I thought I'd throw the idea into the mix.
I thought about that too, and mentioned it yesterday in a reply[1] to you on this list. Here is the link to the Gist with the hypothetical code using such a concept: - https://gist.github.com/mikeschinkel/78684d708358e1d101e319c7a2fdef9c -Mike [1] https://www.mail-archive.com/internals@lists.php.net/msg100719.html
  108559
February 14, 2020 07:04 manuelcanga@gmail.com (Manuel Canga)
On Fri, 14 Feb 2020 at 01:39, Mike Schinkel <mike@newclarity.net> wrote:

> > On Feb 13, 2020, at 7:24 PM, Rowan Tommins collins@gmail.com> > wrote: > > > > An idea I had earlier which might solve some of them is if what was > returned was not a normal Closure instance, but a new class like > FunctionReference. It could then "remember" the name of the function > wrapped, and implement __toString, Serializable, etc. It could inherit from > Closure, so instanceof checks would work, and bindTo would return a normal > Closure. I'm sure there's downsides I haven't thought of yet, but I thought > I'd throw the idea into the mix. > > I thought about that too, and mentioned it yesterday in a reply[1] to you > on this list. > > Here is the link to the Gist with the hypothetical code using such a > concept: > > - https://gist.github.com/mikeschinkel/78684d708358e1d101e319c7a2fdef9c > > -Mike > > > [1] https://www.mail-archive.com/internals@lists.php.net/msg100719.html > > Maybe, bettern fn: * fn(callable $to_clsoure ): *closure ?
I know fn is used in arrow functions. However, for that same reason fn is the most convenient. Using dik examples( by the way, they are brilliant ): $result = Stats::of($string) ->analyze(fn(normalizeNewlines)) ->analyze(fn(readingLevel)) ->analyze(fn(countStats)) ->analyze(fn($synonymSuggester, 'analyze')) ->analyze(fn(WordCouter::class, 'analyze')) ->analyze(fn($s) => wordDistribution($s, 3)) Returning to ::function again and with a modified example of dik( again ): Now is: result = Stats::of($string) ->analyze('\Stats\Analyzer\normalizeNewlines') ->analyze('\Stats\Readings\readingLevel') ->analyze('\Stats\Parser\countStats') ->analyze(fn($s) => \Stats\Analyzer\wordDistribution($s, 3)); Could be: use function Stats\Analyzer\normalizeNewlines; use function \Stats\Readings\readingLevel; use function \Stats\Parser\countStats; result = Stats::of($string) ->analyze(normalizeNewlines::function) ->analyze(readingLevel::function) ->analyze(countStats::function ) ->analyze(fn($s) => \Stats\Analyzer\wordDistribution($s, 3)); Maybe '::function' is something long, however it wiil be autocompleted by editors and, moreover, nowadays function is a reserved keyword. Could we use "normalizeNewlines::name", but in this case: normalizeNewlines is function or class ?, because in this case could be "normalizeNewlines" a class and "name" a constant of class. Rowan put me in an awkward situation with [MyClass::class, method::function ] however, in this case, could be simply MyClass::class, 'method' ]. Because method don't need be used with namespace. ::function could be documented with advice of being used with name of functions. Because ::function is also useful in array: $filters = [ normalizeNewlines::function, readingLevel::function, countStats::function ] $content = Stats::of($string); foreach($filters as $filter) $filter($content); Regards
  108593
February 15, 2020 08:22 larry@garfieldtech.com ("Larry Garfield")
On Fri, Feb 14, 2020, at 1:04 AM, Manuel Canga wrote:

> Maybe, bettern fn: * fn(callable $to_clsoure ): *closure ? > > I know fn is used in arrow functions. However, for that same reason fn is > the most convenient. > > Using dik examples( by the way, they are brilliant ):
Point of order: The Stats analyzer examples were from me, not Dik. :-) They're taken from one of the monad chapters in the book I'm working on. --Larry Garfield
  108594
February 15, 2020 11:51 php@manuelcanga.dev (Manuel Canga)
---- En sáb, 15 feb 2020 09:22:41 +0100 Larry Garfield <larry@garfieldtech.com> escribió ----
 > On Fri, Feb 14, 2020, at 1:04 AM, Manuel Canga wrote:
 > 
 > > Maybe, bettern fn:  * fn(callable $to_clsoure ): *closure ?
 > > 
 > > I know fn is used in arrow functions. However, for that same reason fn is
 > > the most convenient.
 > > 
 > > Using dik examples( by the way, they are brilliant ):
 > 
 > Point of order: The Stats analyzer examples were from me, not Dik. :-)  They're taken from one of the monad chapters in the book I'm working on.
 > 
 > --Larry Garfield


Oops!, sorry Larry!. Then you book will be securily a great book.
  108595
February 15, 2020 12:07 php@manuelcanga.dev (Manuel Canga)
---- En sáb, 15 feb 2020 09:22:41 +0100 Larry Garfield <larry@garfieldtech.com> escribió ----
 > On Fri, Feb 14, 2020, at 1:04 AM, Manuel Canga wrote:
 > 
 > > Maybe, bettern fn:  * fn(callable $to_clsoure ): *closure ?
 > > 
 > > I know fn is used in arrow functions. However, for that same reason fn is
 > > the most convenient.
 > > 
 > > Using dik examples( by the way, they are brilliant ):
 > 
 > Point of order: The Stats analyzer examples were from me, not Dik. :-)  They're taken from one of the monad chapters in the book I'm working on.
 > 
 > --Larry Garfield
 > 

By the way...the following is for folks in internals:

Do you think it is worth creating an RFC page about :: function ? I say that because I see that there are many voices against of :: function
  108601
February 15, 2020 17:01 larry@garfieldtech.com ("Larry Garfield")
On Sat, Feb 15, 2020, at 6:07 AM, Manuel Canga wrote:
> > ---- En sáb, 15 feb 2020 09:22:41 +0100 Larry Garfield > <larry@garfieldtech.com> escribió ---- > > On Fri, Feb 14, 2020, at 1:04 AM, Manuel Canga wrote: > > > > > Maybe, bettern fn: * fn(callable $to_clsoure ): *closure ? > > > > > > I know fn is used in arrow functions. However, for that same > reason fn is > > > the most convenient. > > > > > > Using dik examples( by the way, they are brilliant ): > > > > Point of order: The Stats analyzer examples were from me, not Dik. > :-) They're taken from one of the monad chapters in the book I'm > working on. > > > > --Larry Garfield > > > > By the way...the following is for folks in internals: > > Do you think it is worth creating an RFC page about :: function ? I say > that because I see that there are many voices against of :: function
There seems to be little pushback on the idea of a better way to name/reference functions, so an RFC page for that seems reasonable. What the syntax is, that's still in heavy bikeshed territory, so maybe don't name the RFC based on the implementation detail yet. :-) I'd love to get some input from Nikita or Dimitry or someone else with way more parser experience on how feasible any of the options discussed so far would be; if some are vastly more straightforward than others, that carries a lot of weight. --Larry Garfield
  108611
February 15, 2020 23:25 d.h.j.takken@freedom.nl (Dik Takken)
On 15-02-2020 13:07, Manuel Canga wrote:
> Do you think it is worth creating an RFC page about :: function ? I say that because I see that there are many voices against of :: function
Let us go back to the start of this thread. Your idea was to simplify array_map('\My\I18N\i18n_translate', $array) to array_map(i18n_translate::func, $array) Then the discussion took the topic one level deeper. In your examples, you seek a better way to pass a function as callable. In PHP a callable can be: 1. a string 2. an array 3. a closure Then it was suggested that a short syntax to wrap the function into a closure is more useful. Using strings to refer to functions has consistency issues and the proposed ::func does not solve them. Also, the array syntax for referring to methods could use a better alternative. All things considered, I think the originally proposed feature, using ::func to get the function name, has limited use. Having a ::func (or ::function or ::fn) return a closure might be somewhat controversial and there is no consensus about the name. The only way to know how this will be received is to write an RFC and call for a vote. My own guess would be that an 'enclosure' construct along the lines of array_map({i18n_translate}, $array) array_map({$object->method}, $array) has better chances of succeeding but you never know what happens. Perhaps you could team up with Michał and use the feedback from this thread to produce an RFC. Regards, Dik Takken
  108560
February 14, 2020 08:23 rowan.collins@gmail.com (Rowan Tommins)
On 14 February 2020 00:39:15 GMT+00:00, Mike Schinkel <mike@newclarity.net> wrote:
>> On Feb 13, 2020, at 7:24 PM, Rowan Tommins collins@gmail.com> >wrote: >> >> An idea I had earlier which might solve some of them is if what was >returned was not a normal Closure instance, but a new class like >FunctionReference. It could then "remember" the name of the function >wrapped, and implement __toString, Serializable, etc. It could inherit >from Closure, so instanceof checks would work, and bindTo would return >a normal Closure. I'm sure there's downsides I haven't thought of yet, >but I thought I'd throw the idea into the mix. > >I thought about that too, and mentioned it yesterday in a reply[1] to >you on this list. > >Here is the link to the Gist with the hypothetical code using such a >concept: > >- https://gist.github.com/mikeschinkel/78684d708358e1d101e319c7a2fdef9c
What I had in mind was a combination of that and the existing Closure class, so: $ref = foo::fn; $ref(); // run the function $ref->name; // access extra metadata $ref->bindTo($whatever); // get a new Closure with a bound context That would also combine well with one of the proposed bracket style syntaxes that let you specify methods more naturally: {foo}->name; // qualified name of local function {Foo::bar}; // closure for a static method {$this->baz}->bindTo($that); // closure for a method of current class rebound to a different object Regards, -- Rowan Tommins [IMSoP]