Re: [PHP] Non required argument
Simon J Welsh wrote: [snip] function list_formvars($pmatch=null) {... http://php.net/manual/en/functions.arguments.php#functions.arguments.default Thanks!.. missed that doc somehow. Donovan -- D Brooke -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
[PHP] Variable Troubleshooting Code
Hello!, I work in another language mostly and often develop while displaying variables (post,get,and defined) and their values at the bottom of the page or in specific places. So, I thought I'd forward my PHP version as an effort of good Karma to the list perhaps! ;-) Below is 2 simple functions that are helpful for troubleshooting while developing. Just place this code into a .php file and require it at the top of any PHP page. Then, at the bottom of the page, or in a specific (more pertinent) location, call the functions with something like this: Testing:'; print htmlentities(list_formvars()); print htmlentities(list_vars(get_defined_vars())); print ''; ?> - Optionally, you can call only specific naming conventions of your variables (if you use them).. ie: print htmlentities(list_vars(get_defined_vars(),'t_')); The above will display all defined vars such as: t_name= t_city= t_address= etc.. Code: --- /* FUNCTION NAME: list_formvars INPUT: optional var OUTPUT: = = USE: For troubleshooting code Example Use: list_formvars(); list_formvars('f_a'); */function list_formvars($pmatch = null) { print "'get' Vars:"; foreach ($_GET as $key => $value) { if (isset($pmatch)) { if (substr($key,0,strlen($pmatch)) == $pmatch) { print "$key = $value"; } } else { print "$key = $value"; } } print "'post' Vars:"; foreach ($_POST as $key => $value) { if (isset($pmatch)) { if (substr($key,0,strlen($pmatch)) == $pmatch) { print "$key = $value"; } } else { print "$key = $value"; } } }/* FUNCTION NAME: list_vars INPUT: get_defined_vars(), match OUTPUT: = = USE: For troubleshooting code Example Use: list_vars(get_defined_vars()); list_vars(get_defined_vars(),'t_'); */function list_vars($a_vars,$pmatch = null) { print "'defined' Vars:"; foreach ($a_vars as $key => $value) { if (isset($pmatch)) { if (substr($key,0,strlen($pmatch)) == $pmatch) { print "$key = $value"; } } else { print "$key = $value"; } } } Cheers, Donovan P.S. Always open to good criticism if you peeps see something that can be written better.. this is about my 3rd PHP project only... so, still heavily learning ;-) -- D Brooke -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Variable Troubleshooting Code
Hi, some pretty natives php functions exists to do the job : var_export — Outputs or returns a parsable string representation of a variable debug_zval_dump — Dumps a string representation of an internal zend value to output var_dump — Dumps information about a variable print_r — Prints human-readable information about a variable echo ''; print_r( array | object ); echo ''; Regards. Le 7 janv. 2012 à 19:00, Donovan Brooke a écrit : > Hello!, > I work in another language mostly and often develop while displaying > variables (post,get,and defined) and their values at the bottom of the page > or in specific places. So, I thought I'd forward my PHP version as an effort > of good Karma to the list perhaps! ;-) > > Below is 2 simple functions that are helpful for troubleshooting while > developing. Just place this code into a .php file and require it at the top > of any PHP page. Then, at the bottom of the page, or in a specific (more > pertinent) location, call the functions with something like this: > > > //troubleshooting code > print 'Testing:'; > > print htmlentities(list_formvars()); > > print htmlentities(list_vars(get_defined_vars())); > > print ''; > ?> > - > > Optionally, you can call only specific naming conventions of your variables > (if you use them).. ie: > > print htmlentities(list_vars(get_defined_vars(),'t_')); > > The above will display all defined vars such as: > > t_name= > t_city= > t_address= > > etc.. > > > Code: > --- > /* > FUNCTION NAME: list_formvars > INPUT: optional var > OUTPUT: = > = > USE: For troubleshooting code > > Example Use: > list_formvars(); > list_formvars('f_a'); > > */function list_formvars($pmatch = null) { > print "'get' Vars:"; > foreach ($_GET as $key => $value) { >if (isset($pmatch)) { > if (substr($key,0,strlen($pmatch)) == $pmatch) { > print "$key = $value"; > } >} else { > print "$key = $value"; >} > } > > print "'post' Vars:"; > foreach ($_POST as $key => $value) { >if (isset($pmatch)) { > if (substr($key,0,strlen($pmatch)) == $pmatch) { > print "$key = $value"; > } >} else { > print "$key = $value"; >} > } > }/* > FUNCTION NAME: list_vars > INPUT: get_defined_vars(), match > OUTPUT: = > = > USE: For troubleshooting code > > Example Use: > list_vars(get_defined_vars()); > list_vars(get_defined_vars(),'t_'); > */function list_vars($a_vars,$pmatch = null) { > print "'defined' Vars:"; > foreach ($a_vars as $key => $value) { >if (isset($pmatch)) { > if (substr($key,0,strlen($pmatch)) == $pmatch) { > print "$key = $value"; > } >} else { > print "$key = $value"; >} > } > } > > > Cheers, > Donovan > > > P.S. Always open to good criticism if you peeps see something that can be > written better.. this is about my 3rd PHP project only... so, still heavily > learning ;-) > > > -- > D Brooke > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php >
[PHP] Strange foreach reference issue
Hello, This sure looks like a bug, but maybe there's some subtlety going on that I don't understand, so I would appreciate some insight. After much debugging, I tracked down a bug in my code to this test program. My PHP version is 5.3.3, running under Fedora Linux. 'Title #1', ), array( 'Title' => 'Title #2', ), array( 'Title' => 'Title #3', ) ); print " Rows at start: " . print_r($row_list, true); foreach ($row_list as $idx => &$row) { print "Title A $idx: {$row['Title']}\n"; } print " Rows are now: " . print_r($row_list, true); foreach ($row_list as $idx => $row) { print "Title B $idx: {$row['Title']}\n"; } ?> When you run the program, it gives the following output: -- Rows at start: Array ( [0] => Array ( [Title] => Title #1 ) [1] => Array ( [Title] => Title #2 ) [2] => Array ( [Title] => Title #3 ) ) Title A 0: Title #1 Title A 1: Title #2 Title A 2: Title #3 Rows are now: Array ( [0] => Array ( [Title] => Title #1 ) [1] => Array ( [Title] => Title #2 ) [2] => Array ( [Title] => Title #3 ) ) Title B 0: Title #1 Title B 1: Title #2 Title B 2: Title #2 -- Note that the second foreach repeats the second row, even though the index is correct and the print_r shows things as correct. Now, if you change the name of the reference variable from '$row' to '$rowx' (for example), things will work. So clearly there's some issue with $row being previously used as a reference that's "contaminating" the subsequent use of $row in the foreach. If there's some logic to this, it's escaping me. Any insight on this would be appreciated. Regards, Tim Behrendsen -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Strange foreach reference issue
I cut and pasted your code and got the same result. I flipped the two foreach blocks and got the expected results. I deleted the first block and copied the second, then updated the string. I got this. I can't explain. 'Title #1', ), array( 'Title' => 'Title #2', ), array( 'Title' => 'Title #3', ) ); print " Rows are: " . print_r($row_list, true); foreach ($row_list as $idx => $row) { print "Title A $idx: {$row['Title']}\n"; } print " Rows are now: " . print_r($row_list, true); foreach ($row_list as $idx => $row) { print "Title B $idx: {$row['Title']}\n"; } Rows are: Array ( [0] => Array ( [Title] => Title #1 ) [1] => Array ( [Title] => Title #2 ) [2] => Array ( [Title] => Title #3 ) ) Title A 0: Title #1 Title A 1: Title #2 Title A 2: Title #3 Rows are now: Array ( [0] => Array ( [Title] => Title #1 ) [1] => Array ( [Title] => Title #2 ) [2] => Array ( [Title] => Title #3 ) ) Title B 0: Title #1 Title B 1: Title #2 Title B 2: Title #3 On 12-01-07 06:29 PM, Tim Behrendsen wrote: Hello, This sure looks like a bug, but maybe there's some subtlety going on that I don't understand, so I would appreciate some insight. After much debugging, I tracked down a bug in my code to this test program. My PHP version is 5.3.3, running under Fedora Linux. 'Title #1', ), array( 'Title' => 'Title #2', ), array( 'Title' => 'Title #3', ) ); print " Rows at start: " . print_r($row_list, true); foreach ($row_list as $idx => &$row) { print "Title A $idx: {$row['Title']}\n"; } print " Rows are now: " . print_r($row_list, true); foreach ($row_list as $idx => $row) { print "Title B $idx: {$row['Title']}\n"; } ?> When you run the program, it gives the following output: -- Rows at start: Array ( [0] => Array ( [Title] => Title #1 ) [1] => Array ( [Title] => Title #2 ) [2] => Array ( [Title] => Title #3 ) ) Title A 0: Title #1 Title A 1: Title #2 Title A 2: Title #3 Rows are now: Array ( [0] => Array ( [Title] => Title #1 ) [1] => Array ( [Title] => Title #2 ) [2] => Array ( [Title] => Title #3 ) ) Title B 0: Title #1 Title B 1: Title #2 Title B 2: Title #2 -- Note that the second foreach repeats the second row, even though the index is correct and the print_r shows things as correct. Now, if you change the name of the reference variable from '$row' to '$rowx' (for example), things will work. So clearly there's some issue with $row being previously used as a reference that's "contaminating" the subsequent use of $row in the foreach. If there's some logic to this, it's escaping me. Any insight on this would be appreciated. Regards, Tim Behrendsen -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Strange foreach reference issue
On Sun, Jan 8, 2012 at 12:29 AM, Tim Behrendsen wrote: > Hello, > > This sure looks like a bug, but maybe there's some subtlety going on that I > don't understand, so I would appreciate some insight. After much debugging, > I tracked down a bug in my code to this test program. My PHP version is > 5.3.3, running under Fedora Linux. > > $row_list = array( > array( > 'Title' => 'Title #1', > ), > array( > 'Title' => 'Title #2', > ), > array( > 'Title' => 'Title #3', > ) ); > > print " Rows at start: " . print_r($row_list, true); > foreach ($row_list as $idx => &$row) { Why is there an '&' before $row here? That seems like the problem to me.. Matijn -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Strange foreach reference issue
On 1/7/2012 4:18 PM, Matijn Woudt wrote: On Sun, Jan 8, 2012 at 12:29 AM, Tim Behrendsen wrote: Hello, This sure looks like a bug, but maybe there's some subtlety going on that I don't understand, so I would appreciate some insight. After much debugging, I tracked down a bug in my code to this test program. My PHP version is 5.3.3, running under Fedora Linux. 'Title #1', ), array( 'Title' => 'Title #2', ), array( 'Title' => 'Title #3', ) ); print " Rows at start: " . print_r($row_list, true); foreach ($row_list as $idx => &$row) { Why is there an '&' before $row here? That seems like the problem to me.. Matijn When you use an ampersand on the variable, that creates a reference to the array elements, allowing you to potentially change the array elements themselves (which I'm not doing here). http://www.php.net/manual/en/control-structures.foreach.php I do notice in the manual that it says, "Reference of a $value and the last array element remain even after the foreach loop. It is recommended to destroy it by unset()." But that doesn't really explain why it contaminates the next foreach loop in such an odd way. You would think that the $row in the second loop would be assigned a non-reference value. Tim -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Strange foreach reference issue
On 12-01-07 07:30 PM, Tim Behrendsen wrote: When you use an ampersand on the variable, that creates a reference to the array elements, allowing you to potentially change the array elements themselves (which I'm not doing here). http://www.php.net/manual/en/control-structures.foreach.php I do notice in the manual that it says, "Reference of a $value and the last array element remain even after the foreach loop. It is recommended to destroy it by unset()." But that doesn't really explain why it contaminates the next foreach loop in such an odd way. You would think that the $row in the second loop would be assigned a non-reference value. Tim Tim, You are using the &$variable in an unintended (by PHP designers), and I suggest undefined manner. So the outcome cannot, but definition be explained. Was this intended, and what were you trying to accomplish? Stephen -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Strange foreach reference issue
On 1/7/2012 4:44 PM, Stephen wrote: On 12-01-07 07:30 PM, Tim Behrendsen wrote: When you use an ampersand on the variable, that creates a reference to the array elements, allowing you to potentially change the array elements themselves (which I'm not doing here). http://www.php.net/manual/en/control-structures.foreach.php I do notice in the manual that it says, "Reference of a $value and the last array element remain even after the foreach loop. It is recommended to destroy it by unset()." But that doesn't really explain why it contaminates the next foreach loop in such an odd way. You would think that the $row in the second loop would be assigned a non-reference value. Tim Tim, You are using the &$variable in an unintended (by PHP designers), and I suggest undefined manner. So the outcome cannot, but definition be explained. Was this intended, and what were you trying to accomplish? Stephen In the real code, I just happen to use the same variable name first as a reference, and then as a normal non-reference, and was getting the mysterious duplicate rows. I think I'm using everything in a completely reasonable way; the second foreach is reassigning the loop variable. Nothing that comes before using that variable ought to cause undefined behavior. The warning in the manual is about using the loop variable as a reference after exiting the loop, but I'm not doing that. I'm reassigning it, exactly as if I just decided to do a straight assignment of "$row" Ah ha, wait a minute, that's the key. OK, this is making more sense. The first loop is leaving a reference to the final element. But then the second foreach is doing a straight assignment to the $row variable, but $row is a reference to the final element. So the foreach is assigning its iterated value to the final element of the array, instead of a normal variable. OK, I understand the logic now. The world now makes sense. The moral is always unset the iterator variable when doing foreach with a reference, like the manual says. :) Thanks for everyone's help. Tim -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php