Provided by: libverilog-perl_3.460-1_amd64 bug


       Verilog::Preproc - Preprocess Verilog files


           use Verilog::Getopt;

           my $vp = Verilog::Preproc->new(I<parameters>);
           my $line = $vp->getline();


           # This is a complete verilog pre-parser!
           # For a command line version, see vppreproc
           use Verilog::Getopt;
           use Verilog::Preproc;

           my $opt = new Verilog::Getopt;
           @ARGV = $opt->parameter(@ARGV);

           my $vp = Verilog::Preproc->new(options=>$opt,);
           while (defined (my $line = $vp->getline())) {
              print $line;


       Verilog::Preproc reads Verilog files, and preprocesses them according to the SystemVerilog
       2009 (1800-2009) specification.  Programs can be easily converted from reading a IO::File
       into reading preprocessed output from Verilog::Preproc.

       See the "Which Package" section of Verilog-Perl if you are unsure which parsing package to
       use for a new application.


           Returns true at the end of the file.

           Returns the filename of the most recently returned getline().  May not match the
           filename passed on the command line, as `line directives are honored.

           Return the entire translated text up to the final EOF, similar to calling
           join('',$self->getline) but significantly faster.  With optional argument, returns
           approximately that number of characters.  Returns undef at EOF.

           Return the next line of text.  Returns undef at EOF.  (Just like IO::File->getline().)

           Returns the line number of the last getline().  Note that the line number may change
           several times between getline(), for example when traversing multiple include files.

           Returns a reference to the Verilog::Netlist::File which created this object, if any.

           Creates a new preprocessor.  See the PARAMETERS section for the options that may be
           passed to new.

           Opens the specified file.  If filename ends in .gz, decompress while reading.  If
           called before a file is completely parsed, the new file will be parsed completely
           before returning to the previously open file.  (As if it was an include file.)

           Open may also be called without named parameters, in which case the only argument is
           the filename.

           Insert text into the input stream at the given point.  The text will not be parsed,
           just returned to the application.  This lets comment() callbacks insert special code
           into the output stream.


       The following named parameters may be passed to the new constructor.

           With ieee_predefines false, disable defining SV_COV_START and other IEEE mandated

           With include_open_nonfatal set to one, ignore any include files that do not exist.

           With keep_comments set to zero, strip all comments.  When set to one (the default),
           insert comments in output streams.  When set to 'sub', call the comment() function so
           that meta-comments can be processed outside of the output stream.  Note that some
           programs use meta-comments to embed useful information (synthesis and lint), so strip
           with caution if feeding to tools other than your own.  Defaults to 1.

           With keep_whitespace set to zero, compress all whitespace to a single space or
           newline.  When set to one (the default), retain whitespace.  Defaults to 1.

           With line_directives set to zero, suppress "`line" comments which indicate filename
           and line number changes.  Use the lineno() and filename() methods instead to retrieve
           this information. Defaults true.

       options=>Verilog::Getopt object
           Specifies the object to be used for resolving filenames and defines.  Other classes
           may be used, as long as their interface matches that of Getopt.

           With pedantic set, rigorously obey the Verilog pedantic.  This used to disable the
           `__FILE__ and `__LINE__ features but no longer does as they were added to the
           1800-2009 standard.  It remains to disable `error and may disable other future
           features that are not specified in the language standard. Defaults false.

           With synthesis set, define SYNTHESIS, and ignore text bewteen "ambit", "pragma",
           "synopsys" or "synthesis" translate_off and translate_on meta comments.  Note using
           metacomments is discouraged as they have led to silicon bugs (versus ifdef SYNTHESIS);
           see <>.


       Default callbacks are implemented that are suitable for most applications.  Derived
       classes may override these callbacks as needed.

           Called with each comment, when keep_comments=>'sub' is used.  Defaults to do nothing.

           Called with each `undef.  Defaults to use options object.

           Called with each `undefineall.  Defaults to use options object.

       $self->define(defname, value, params)
           Called with each `define.  Defaults to use options object.

           Called to determine if the define exists.  Return true if the define exists, or
           argument list with leading parenthesis if the define has arguments.  Defaults to use
           options object.

           Called to determine what string to insert for a define substitution.  Called with the
           value of the define after parameters have been expanded computed per the SystemVerilog
           spec.  Generally this function would just return the same string as it is passed, but
           this can be overridden to allow customized preprocessing.

           Called to return value to substitute for specified define.  Defaults to use options

           Called on errors, with the error message as an argument.  Defaults to die.

           Specifies a include file has been found.  Defaults to call $self->open after resolving
           the filename with the options parameter.


       The preprocessor supports the constructs defined in the SystemVerilog 2017 standard (IEEE
       1800-2017), which is a superset of Verilog 1995 (IEEE 1364-1995), Verilog 2001 (IEEE
       1364-2001), Verilog 2005 (IEEE 1364-2005) SystemVerilog 2005 (IEEE 1800-2005),
       SystemVerilog 2009 (IEEE 1800-2009), and SystemVerilog 2012 (IEEE 1800-2012).

       Verilog::Preproc adds the `error macro (unless the pedantic parameter is set.):

           The __FILE__ define expands to the current filename as a string, like C++'s __FILE__.
           This was incorporated into to the 1800-2009 standard (but supported by Verilog-Perl
           since 2004!)

           The __LINE__ define expands to the current filename as a string, like C++'s __LINE__.
           This was incorporated into to the 1800-2009 standard (but supported by Verilog-Perl
           since 2004!)

       `error "string"
           `error will be reported whenever it is encountered. (Like C++ #error.)

           These are useful for error macros, similar to assert() in C++.


       Verilog-Perl is part of the <> free Verilog EDA software tool
       suite.  The latest version is available from CPAN and from

       Copyright 2000-2019 by Wilson Snyder.  This package is free software; you can redistribute
       it and/or modify it under the terms of either the GNU Lesser General Public License
       Version 3 or the Perl Artistic License Version 2.0.


       Wilson Snyder <>


       Verilog-Perl, Verilog::Language, Verilog::Getopt


       This package is layered on a C++ interface which may be found in the kit.