Re: IDL compatibility

["Mark Hadfield" <m.hadfield(at)niwa.cri.nz>]

"Craig Markwardt" <craigmnet@cow.physics.wisc.edu> wrote in message
onpuhvhv1v.fsf@cow.physics.wisc.edu">news:onpuhvhv1v.fsf@cow.physics.wisc.edu...
> [stuff about commonly-used IDL routines being made obsolete]

Just adding to Craig's message (with which I fully agree) perhaps not
everyone is aware of the !WARN system variable. From the documentation:

!WARN

A structure variable that causes IDL to print warnings to the console or
command log when obsolete IDL features are found at compile time. !WARN has
the following fields:

*****
** Structure !WARN, 3 tags, length=3:

   OBS_ROUTINES         BYTE         0
   OBS_SYSVARS          BYTE         0
   PARENS               BYTE         0
   TRUNCATED_FILENAME   BYTE         0

Setting each of the four fields to 1 (one) generates a warning for a
different type of obsolete code [remainder deleted]
*****

A routine is considered to be obsolete if it has "compile_opt OBSOLETE" in
the header or if its .pro file is in a directory named "obsolete".

By the way, I find it amusing that in if !warn.obs_sysvars is set in IDL
5.3, then several warning messages are produced in compiling XMANAGER! This
has been fixed in version 5.4.

---
Mark Hadfield
m.hadfield@niwa.cri.nz  http://katipo.niwa.cri.nz/~hadfield/
National Institute for Water and Atmospheric Research
PO Box 14-901, Wellington, New Zealand