ExtUtils::XSSymSet(3p) Perl Programmers Reference Guide #

ExtUtils::XSSymSet(3p) Perl Programmers Reference Guide

NNAAMMEE #

 ExtUtils::XSSymSet - keep sets of symbol names palatable to the VMS
 linker

SSYYNNOOPPSSIISS #

   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);

DDEESSCCRRIIPPTTIIOONN #

 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 _x_s_u_b_p_p 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 aaddddssyymm(())
     or ttrriimmssyymm(()) 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
     ttrriimmssyymm(()), 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 aaddddssyymm(()) 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 aaddddssyymm(()).  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 aaddddssyymm(()), 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 aaddddssyymm(()), or "undef" if $name is not a member of this set of
     symbols.  This method must be called via an existing object.

 aallll__oorriigg(())
     Returns a list containing all of the original symbol names from this
     set.

 aallll__ttrriimmmmeedd(())
     Returns a list containing all of the trimmed symbol names from this
     set.

AAUUTTHHOORR #

 Charles Bailey  <_b_a_i_l_e_y_@_n_e_w_m_a_n_._u_p_e_n_n_._e_d_u>

RREEVVIISSIIOONN #

 Last revised 8-Oct-2010, for Perl 5.13.6.

perl v5.36.3 2019-02-13 ExtUtils::XSSymSet(3p)