TYPO3 Core

That's true for this method but not for the similar method in tsparser_ext (you didn't mention here), so I will only change the method in t3lib_tstemplate

(don't ask me why)

I think the same logic can be apply into substituteConstants in tsparser_ext
You just have to wrote two more different callback.

Beside, Why put the switch in the loop??
put it outside the loop can be faster.
(i.e. It still do loop on the flatSetup even "untouched")
----
function substituteConstantsConstCallBack($matches) {
if(isset ($this->flatSetup[$matches¹])){
return '##'.$this->Cmarker.'_B##{$'.$matches⁰.'}##'.$this->Cmarker.'_E##';
}else{
return $matches⁰;
}
}
function substituteConstantsSubstCallBack($matches) {
if(isset ($this->flatSetup[$matches¹])){
return '##'.$this->Cmarker.'_B##{$'.$this->flatSetup[$matches¹].'}##'.$this->Cmarker.'_E##';
}else{
return $matches⁰;
}
}
function substituteConstantsCallBack($matches) {
return isset ($this->flatSetup[$matches¹]) ? $this->flatSetup[$matches¹] : $matches⁰;
}
function substituteConstants($all) {
switch($this->constantMode) {
case 'untouched':
return all;
case 'const':
$this->Cmarker=substr(md5(uniqid("")),0,6);
return preg_replace_callback('/\{\$(.+?)\}/', array ($this, 'substituteConstantsConstCallBack'), $all);
case 'subst':
$this->Cmarker=substr(md5(uniqid("")),0,6);
return preg_replace_callback('/\{\$(.+?)\}/', array ($this, 'substituteConstantsSubstCallBack'), $all);
default:
return preg_replace_callback('/\{\$(.+?)\}/', array ($this, 'substituteConstantsCallBack'), $all);
}
}

function substituteCMarkers($all)    {
        switch($this->constantMode)    {
            case 'const':
            case 'subst':
                $all = str_replace(
                    array('##'.$this->Cmarker.'_B##','##'.$this->Cmarker.'_E##'),
                    array('<font color="green"><B>','</b></font>'),
                    $all);
            default:
        }
        return $all;
    }

I found a bug in my test code, sorry, I'll post it ASAP to the core list.

fixed in CVS

When CVS version 1.27.2.2 is used as in TYPO3 4.0RC1, constants are not correctly replaced.

In the case I encountered, constants assigned to other constants are not correctly replaced.

Reverting to 1.27.2.1 corrects the problem.

In the case I encountered, constants assigned to other constants are not correctly replaced.

In fact, the old substituteConstants was not correctly replaced too.

The "constants assigned to other constants" should be resloved and report error for any recursive loop.

I forget I did modified some where else, and make it reslove "constants assigned to other constants" at constant parse time. ( It does make sense and faster)

-----
What SHOULD the ideal final value in the folloing example?

$abc=abc
$useabc={$abc}
$abc=def

$x=x
$y=y
$xyz=${x}${y}${z}
$z=z

$inner=inner
$inner2=inner2
$outer={${$inner}2}

I'll take a look at it asap

Please test the attached patch (bug2743_followup.diff), this should fix the issue with constants in constants.

I'll commit it to CVS if no one complains.

Patch looks good to me, but please add some comments that explain why you are going three times over the loop (I suppose this is just an assumption?)

That's just a reasonable value, I don't think that anybody out there will ever cascade more than 3 levels of constants;
this is possible now:

TEST4 = Kaviar
TEST3 = Bananen, aber keinen {$TEST4}
TEST1 = Affen {$TEST2}
TEST2 = essen gerne {$TEST3}

this will output

Affen essen gerne Bananen, aber keinen {$TEST4}

We can easily increase to let's say 5 as the loop will end if there's no further substitution possible anyway...

btw: prior to this patch the following is not possible:

TEST2 = Test
TEST1 = das ist ein {$TEST2}

das ist ein {$TEST2}

while this:

TEST1 = das ist ein {$TEST2}
TEST2 = Test

das ist ein Test

so this "issue" is gone now too!

@hkdennis2k:

-------------------------
abc=abc
useabc={$abc}
abc=def

page.500 = TEXT
page.500.value = {$useabc} 

Output: def
-------------------------
x=x
y=y
xyz={$x}{$y}{$z}
z=z

page.500 = TEXT
page.500.value = {$xyz} 

Output: xyz
-------------------------
inner=inner
inner2=inner2
outer={${$inner}2}

page.500 = TEXT
page.500.value = {$outer} 

Output: {${$inner}2}
-------------------------

so the last one will not work (and did not before)

I suggest you set the loop limit to 99 then so we will definitely never have any problems.

Please commit the patch to CVS so it is fixed there, but send a copy of the patch to the core list for information.

Thanks for providing a solution so quickly!

fixed in CVS, please update,

I set the limit to 10, that should really be enough and make no problems if there's a hidden recursion somewhere
(e.g.

TEST2 = Hello {$TEST2}