XYplorer Beta Club

Posted: **18 Jul 2014 23:40**

Hi,

I build up a set of "growing" variables dynamically in a loop at runtime using the dereference operator (because I use the variable names also as keys to .ini file values), something like that:

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  $ALL_KEYS = "distance|duration|average_pace|total_height|trackpoints"; 
  foreach ($key, $ALL_KEYS) {
    $var = "$".$key;
    // collect raw data per section
    $value = getkey($key, $label, $tfo_file);
    if ($value != "t.b.d.") {
      *$var = eval($var) . "$value|";
    }
  }
  *$var = trim(eval($var), "|");

note: the vars got initialized to "" in an upstream loop

Now I wonder, why this works

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msg("$var: " . eval($var), "1");

but this doesn't

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msg("$var: " . *$var, "1");

I don't get it - especially because each var is eval'ed at the end of it's corresponding write access loop (last statement in 1st code block).

Is it just syntactic incompleteness or a basic logical misunderstanding on my side?

Cheers,
Filehero

PS:

Posted: **19 Jul 2014 01:01**

I don't really understand what you want to do. So made a test...

No loop, no file-read, just some statements:

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 $Name = ""; // init empty

 $key = "Name";   // a var name
 $var = "$".$key; // prefix $
 $value = "Wert"; // assume a value
 *$var = eval($var) . "$value|"; // concatenate

 *$var = trim(eval($var), "|");  // cleanup

 msg("$var: " .eval($var), "1");
 msg("$var: " . *$var, "1");

This shows what I'd expect to happen.

And: I think eval($var) is identical to *$var
(And "1" is identical to 1)

But maybe I missed something?

Posted: **19 Jul 2014 07:37**

Hi Peter

PeterH wrote:....This shows what I'd expect to happen.

And: I think eval($var) is identical to *$var
(And "1" is identical to 1)

But maybe I missed something?

I also consider both statments to be equivalent and expect them both to show

eval_var.png

However, for

Code: Select all

  msg("$var: " . *$var, "1");

I get

deref_var.png

This confuses me. But maybe the statements simply aren't equivalent?

Cheers,
Filehero

Posted: **19 Jul 2014 09:43**

Indeed, a bug!

Fix comes.

Posted: **19 Jul 2014 11:14**

admin wrote:Indeed, a bug! Fix comes.

Fixed, thanks.

Btw, one of the rare times where I welcomed a bug, because otherwise it had proven I still hadn't got the dereference thingie.

Cheers,
Filehero

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[SC] Variable name contain <var>

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