function to cut strings

[madrazel]

i just made this little fella:

 

function strcut($x,$y,$z) {
if ($z=="<-") return strstr($x,$y);
if ($z=="(-") return substr(strstr($x,$y),strlen($y),strlen($x));
if ($z=="->") return strrev(strstr(strrev($x),strrev($y)));
if ($z=="-)") return strrev(substr(strstr(strrev($x),strrev($y)),strlen($y),strlen($x)));
if ($z=="<") return $y.strrev(substr(strrev($x),0,strpos($x,$y)));
if ($z=="(") return strrev(substr(strrev($x),0,strpos($x,$y)));
if ($z==">") return substr($x,0,strpos($x,$y)).$y;
if ($z==")") return substr($x,0,strpos($x,$y));
};

echo strcut("abcXYdefXYghi","XY",")");

 

it works like this:

string: abcXYdefXYghi

 

<- = XYdefXYghi
(- = defXYghi
-> = abcXYdefXY
-) = abcXYdef
< = XYghi
( = ghi
> = abcXY
) = abc

 

any ideas to improve it ?

[taith]

not to be pushy... but wouldnt it be alot... more... robust if you cut your strings seperatly? you have to give the dimensions and the style of your cuts with that function anyways...?

[madrazel]

sorry, i forgot...

 

function strcut($x,$y,$z) {
if ($z=="<-") { return strstr($x,$y); }
elseif ($z=="(-") {return substr(strstr($x,$y),strlen($y),strlen($x));}
elseif ($z=="->") {return strrev(strstr(strrev($x),strrev($y)));}
elseif ($z=="-)") {return strrev(substr(strstr(strrev($x),strrev($y)),strlen($y),strlen($x)));}
elseif ($z=="<") {return $y.strrev(substr(strrev($x),0,strpos($x,$y)));}
elseif ($z=="(") {return strrev(substr(strrev($x),0,strpos($x,$y)));}
elseif ($z==">") {return substr($x,0,strpos($x,$y)).$y;}
elseif ($z==")") {return substr($x,0,strpos($x,$y));}
};

[taith]

ohya... switch() is going to be faster then your if()elsif()'s... might wanna switch to that :-)

[madrazel]

ok, now i done it,:

 

// x - haystack, y - needle, z - mode
function strcut($x,$y,$z) {
switch ($z) {
case '<-': return strstr($x,$y);
case '(-': return substr(strstr($x,$y),strlen($y),strlen($x));
case '->': return strrev(strstr(strrev($x),strrev($y)));
case '-)': return strrev(substr(strstr(strrev($x),strrev($y)),strlen($y),strlen($x)));
case '<' : return $y.strrev(substr(strrev($x),0,strpos($x,$y)));
case '(' : return strrev(substr(strrev($x),0,strpos($x,$y)));
case '>' : return substr($x,0,strpos($x,$y)).$y;
case ')' : return substr($x,0,strpos($x,$y));
default  :  echo "ERROR IN STRCUT"; break;};
};

//testing
$z = array('<-','(-','->','-)','<','(','>',')',);
$x = '123-XY-456-XY-789';
foreach ($z as $z) { echo $z.'  =   '.strcut($x,'XY',$z)."\n"; }

//output
//<-  =   XY-456-XY-789
//(-  =   -456-XY-789
//->  =   123-XY-456-XY
//-)  =   123-XY-456-
//<  =   XY-789
//(  =   -789
//>  =   123-XY
//)  =   123-

 

the question is actually about particular expresiions, i want to avoit things like these:

strrev(substr(strstr(strrev($x),strrev($y)),strlen($y),strlen($x)))