Perl

• Written by Alex Wong. Maintained and improved by Roger Critchlow, Jeremy Yang, Margaret Kamphorst and Jack Delany.
• Doesn't require DaySWIG or SWIG.
• The numerous example programs include applications programs, utilities and CGIs.
• Recent improvements have made installation reasonably straight forward and reliable.
• The wrapper and programs are widely used and very well-tested.
• DayPerl is thin and not highly "Perl-like":
  • Illegal syntax: constants are implemented using functions (e.g. NULL_OB), not scalars, precluding the use of "use strict" for debugging.
  • Single return values (not multiple).
  • The "invalid string" (analogous to NULL in C) is awkwardly handled using the "KLUDGE_INVALID_STRING" pseudo-constant rather than "undef" (e.g. dt_alloc_string("KLUDGE_INVLID_STRING") ).
  • No garbage collection ( dt_dealloc() required to free memory) .
  • Manual error checking.
• Uses null-terminated scalars (SvPV); length needn't be passed to functions (e.g. dt_smilin("OCC")).
• No drawing library (stubs only).

• Written by Craig James.
• Requires SWIG.
• Includes several example programs.
• Is complicated to install (at least on non-Linux Operating Systems).
• Has many dependancies: SWIG, freetype, gnumake (required for freetype).
• Not well-tested by Daylight
• DayPerl2 is somewhat more "Perl-like":
  • Constants are properly implemented as scalar variables (e.g. $NULL_OB ), allowing the use of "use strict" for debugging.
  • Multiple return values are used (e.g. ($ok,$status) = dt_continue($server) ).
  • The "invalid string" is handled in the expected way, using "undef" (e.g. dt_alloc_string(undef)).
  • Uses null-terminated scalars (SvPV); length needn't be passed to functions (e.g. dt_smilin("OCC")).
• No garbage collection ( dt_dealloc() required to free memory) .
• Manual error checking.
• Includes a PNG drawing library.

#!/usr/bin/env perl

use DayPerl;

my ( $mol, $smiles, $cansmi);
 while ($smiles = <STDIN>) {
   chomp $smiles;
   if (NULL_OB == ($mol = dt_smilin($smiles))) {
     print STDERR "ERROR: (dt_smilin) Can't parse SMILES \"$_\"\n";
   } else {
     $cansmi = dt_cansmiles($mol, 1);
     if (!$cansmi) {
       print STDERR "ERROR: (dt_cansmi) \"$_\"\n";
     } else {
       print $cansmi, "\n";
     }
   } 
   dt_dealloc($mol);
 }
exit 0

#!/usr/bin/env perl

use strict;
use DayPerl2;

my ( $mol, $smiles, $cansmi);
 while ($smiles = <STDIN>) {
   chomp $smiles;
   if ($NULL_OB == ($mol = dt_smilin($smiles))) {
     print STDERR "ERROR: (dt_smilin) Can't parse SMILES \"$_\"\n";
   } else {
     if (!$cansmi) {
       print STDERR "ERROR: (dt_cansmi) \"$_\"\n";
     } else {
       print $cansmi, "\n";
     }
   } 
   dt_dealloc($mol);
 }
exit 0