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ExtUtils::XSSymSet(3pm)Perl Programmers Reference GuideExtUtils::XSSymSet(3pm)
NAME
       ExtUtils::XSSymSet - keep sets of symbol names palatable to the VMS
       linker
SYNOPSIS
         use ExtUtils::XSSymSet;
         $set = new ExtUtils::XSSymSet;
         while ($sym = make_symbol()) { $set->addsym($sym); }
         foreach $safesym ($set->all_trimmed) {
           print "Processing $safesym (derived from ",
               $self->get_orig($safesym), ")\n";
           do_stuff($safesym);
         }
         $safesym = ExtUtils::XSSymSet->trimsym($onesym);
DESCRIPTION
       Since the VMS linker distinguishes symbols based only on the first 31
       characters of their names, it is occasionally necessary to shorten
       symbol names in order to avoid collisions.  (This is especially true of
       names generated by xsubpp, since prefixes generated by nested package
       names can become quite long.)  "ExtUtils::XSSymSet" provides functions
       to shorten names in a consistent fashion, and to track a set of names
       to insure that each is unique.  While designed with xsubpp in mind, it
       may be used with any set of strings.
       This package supplies the following functions, all of which should be
       called as methods.
       new([$maxlen[,$silent]])
           Creates an empty "ExtUtils::XSSymset" set of symbols.  This
           function may be called as a static method or via an existing
           object.  If $maxlen or $silent are specified, they are used as the
           defaults for maximum name length and warning behavior in future
           calls to addsym() or trimsym() via this object.  If the compiler
           has been instructed to do its own symbol shortening via
           $Config{'useshortenedsymbols'}, a value of 2048 is assumed for
           $maxlen as a way of bypassing the shortening done by this module.
       addsym($name[,$maxlen[,$silent]])
           Creates a symbol name from $name, using the methods described under
           trimsym(), which is unique in this set of symbols, and returns the
           new name.  $name and its resultant are added to the set, and any
           future calls to addsym() specifying the same $name will return the
           same result, regardless of the value of $maxlen specified.  Unless
           $silent is true, warnings are output if $name had to be trimmed or
           changed in order to avoid collision with an existing symbol name.
           $maxlen and $silent default to the values specified when this set
           of symbols was created.  This method must be called via an existing
           object.
       trimsym($name[,$maxlen[,$silent]])
           Creates a symbol name $maxlen or fewer characters long from $name
           and returns it. If $name is too long, it first tries to shorten it
           by removing duplicate characters, then by periodically removing
           non-underscore characters, and finally, if necessary, by
           periodically removing characters of any type.  $maxlen defaults to
           31.  Unless $silent is true, a warning is output if $name is
           altered in any way.  This function may be called either as a static
           method or via an existing object, but in the latter case no check
           is made to insure that the resulting name is unique in the set of
           symbols.    If the compiler has been instructed to do its own
           symbol shortening via $Config{'useshortenedsymbols'}, a value of
           2048 is assumed for $maxlen as a way of bypassing the shortening
           done by this module.
       delsym($name)
           Removes $name from the set of symbols, where $name is the original
           symbol name passed previously to addsym().  If $name existed in the
           set of symbols, returns its "trimmed" equivalent, otherwise returns
           "undef".  This method must be called via an existing object.
       get_orig($trimmed)
           Returns the original name which was trimmed to $trimmed by a
           previous call to addsym(), or "undef" if $trimmed does not
           correspond to a member of this set of symbols.  This method must be
           called via an existing object.
       get_trimmed($name)
           Returns the trimmed name which was generated from $name by a
           previous call to addsym(), or "undef" if $name is not a member of
           this set of symbols.  This method must be called via an existing
           object.
       all_orig()
           Returns a list containing all of the original symbol names from
           this set.
       all_trimmed()
           Returns a list containing all of the trimmed symbol names from this
           set.
AUTHOR
       Charles Bailey  <bailey AT newman.edu>
REVISION
       Last revised 8-Oct-2010, for Perl 5.13.6.
perl v5.26.3                      2018-03-01           ExtUtils::XSSymSet(3pm)