Re: [RFC] Pipe Operator

On 04/30/2016 06:14 PM, Rowan Collins wrote:

On 29/04/2016 20:58, Sara Golemon wrote: Let's say I want to add a condition just before getFileArg(); with the current version I've got to: - go to the beginning of the chain, and assign to something other than $ret - go to where I want to break the chain, and reintroduce the $ret assignment - add my check in the gap, using the variable I just added at the beginning of the chain $fileList = scandir($arg)

     |> array_filter($$, function($x) { return $x !== '.' && $x != '..'; })
     |> array_map(function ($x) use ($arg) { return $arg . '/' . $x; },

$$); if ( someCheck($fileList) {

     something();

} $ret = getFileArg($$)

     |> array_merge($ret, $$);

The syntax is fighting me here, making me jump around the code. But if assignment was always on the end of the chain, I would only need to make changes at the point where I was breaking the chain. The basic pattern would be: |=> $tempVar; // terminate the chain and capture the value // do stuff with $tempVar $tempVar // restart the chain So: scandir($arg)

     |> array_filter($$, function($x) { return $x !== '.' && $x != '..'; })
     |> array_map(function ($x) use ($arg) { return $arg . '/' . $x; }, $$)
     |=> $fileList;

if ( someCheck($fileList) {

     something();

} $fileList

     |> getFileArg($$)
     |> array_merge($ret, $$)
     |=> $ret;

If I don't need the condition any more, I can delete lines 4 to 8, and I've got back my original chain.

Could you use a closure instead to accomplish this? (Again yes, Sara could you clarify if this is permitted?) $ret = scandir($arg)

        |> array_filter($$, function($x) { return $x !== '.' && $x != '..'; })
        |> array_map(function ($x) use ($arg) { return $arg . '/' . $x; }, $$)
        |> (function($fileList) {
               if (someCheck($fileList)) {
                   something();
               }
               return $fileList;
           })($$)
        |> getFileArg($$)
        |> array_merge($ret, $$);

Not completely the best, but perhaps there's some sort of an idea here? -- Stephen