(un)setting environment variables from a Portfile

[Ian Wadham]

In case anyone does not already know, QTDIR is an env variable
a developer can use when developing software based on Qt or
a development (test, non-standard) version of Qt.

I always export QTDIR=/opt/local when I am developing or building
with a bleeding-edge version of KDE libraries, externally to MacPorts.
If I built my own Qt (heaven forbid, it takes too long), I would point QTDIR
to the root directory of that Qt.

So yes, a "foreign" QTDIR value would not be a good thing to have around
when building Qt...

@René: I am hoping I will be able to point QTDIR to *either* qt4-mac
or qt5-mac when developing and testing KDE apps in the future, as
MacPorts goes through the transition from KDE 4 to KF 5.  I am worried
that having one Qt in /opt/local and another in /opt/local/libexec will not
achieve that cleanly… :-(  Also, I am hoping that there will be Qt apps
in /Applications/MacPorts/Qt5 that are different from the ones already
in the Qt4 subdir, such as an Assistant.app that finds, indexes, searches
and browses Qt 5's documentation not Qt 4's and a Designer.app that
outputs form-designs in whatever file-format is used by Qt 5.

On 12/01/2015, at 7:03 AM, René J.V. Bertin wrote:
> On Sunday January 11 2015 14:49:21 Michael Dickens wrote:
> 
>> PortGroup (qt4; I assume qt5 too), you'll see an "if" statement:
>> {{{
>> if {![info exists building_qt4]} {
>>    configure.env-append \
>>        QTDIR=${qt_dir} \
>>        QMAKE=${qt_qmake_cmd} \
>>        QMAKESPEC=${qt_qmake_spec} \
>>        MOC=${qt_moc_cmd}
>> ....
>> }}}
> 
> AHEM, right. I had noticed the QMAKE* and MOC lines, even ... :-/

All the best, Ian W.