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<div class="document" id="ctags-optlib">
<span id="ctags-optlib-7"></span>
<h1 class="title">ctags-optlib</h1>
<h2 class="subtitle" id="universal-ctags-parser-definition-language">Universal Ctags parser definition language</h2>
<table class="docinfo" frame="void" rules="none">
<col class="docinfo-name" />
<col class="docinfo-content" />
<tbody valign="top">
<tr><th class="docinfo-name">Version:</th>
<td>5.9.0</td></tr>
<tr class="manual-group field"><th class="docinfo-name">Manual group:</th><td class="field-body">Universal Ctags</td>
</tr>
<tr class="manual-section field"><th class="docinfo-name">Manual section:</th><td class="field-body">7</td>
</tr>
</tbody>
</table>
<div class="section" id="synopsis">
<h1>SYNOPSIS</h1>
<div class="line-block">
<div class="line"><strong>ctags</strong> [options] [file(s)]</div>
<div class="line"><strong>etags</strong> [options] [file(s)]</div>
</div>
</div>
<div class="section" id="description">
<h1>DESCRIPTION</h1>
<p><em>Exuberant Ctags</em>, the ancestor of <em>Universal Ctags</em>, has provided
the way to define a new parser from command line. Universal Ctags
extends and refines this feature. <em>optlib parser</em> is the name for such
parser in Universal Ctags. "opt" intends a parser is defined with
combination of command line options. "lib" intends an optlib parser
can be more than ad-hoc personal configuration.</p>
<p>This man page is for people who want to define an optlib parser. The
readers should read ctags(1) of Universal Ctags first.</p>
<p>Following options are for defining (or customizing) a parser:</p>
<ul class="simple">
<li><tt class="docutils literal"><span class="pre">--langdef=<name></span></tt></li>
<li><tt class="docutils literal"><span class="pre">--map-<LANG>=[+|-]<extension>|<pattern></span></tt></li>
<li><tt class="docutils literal"><span class="pre">--kinddef-<LANG>=<letter>,<name>,<description></span></tt></li>
<li><tt class="docutils literal"><span class="pre">--regex-<LANG>=/<line_pattern>/<name_pattern>/<kind-spec>/[<flags>]</span></tt></li>
<li><tt class="docutils literal"><span class="pre">--mline-regex-<LANG>=/<line_pattern>/<name_pattern>/<kind-spec>/[<flags>]</span></tt></li>
</ul>
<p>Following options are for controlling loading parser definition:</p>
<ul class="simple">
<li><tt class="docutils literal"><span class="pre">--options=<pathname></span></tt></li>
<li><tt class="docutils literal"><span class="pre">--options-maybe=<pathname></span></tt></li>
<li><tt class="docutils literal"><span class="pre">--optlib-dir=[+]<directory></span></tt></li>
</ul>
<p>The design of options and notations for defining a parser in
Exuberant Ctags may focus on reducing the number of typing by user.
Reducing the number of typing is important for users who want to
define (or customize) a parser quickly.</p>
<p>On the other hand, the design in Universal Ctags focuses on
maintainability. The notation of Universal Ctags is redundant than
that of Exuberant Ctags; the newly introduced kind should be declared
explicitly, (long) names are approved than one-letter flags
specifying kinds, and naming rules are stricter.</p>
<p>This man page explains only stable options and flags. Universal Ctags
also introduces experimental options and flags which have names starting
with <tt class="docutils literal">_</tt>. For documentation on these options and flags, visit
Universal Ctags web site at <a class="reference external" href="https://ctags.io/">https://ctags.io/</a>.</p>
<div class="section" id="storing-a-parser-definition-to-a-file">
<h2>Storing a parser definition to a file</h2>
<p>Though it is possible to define a parser from command line, you don't
want to type the same command line each time when you need the parser.
You can store options for defining a parser into a file.</p>
<p>ctags loads files (preload files) listed in "FILES"
section of ctags(1) at program starting up. You can put your parser
definition needed usually to the files.</p>
<p><tt class="docutils literal"><span class="pre">--options=<pathname></span></tt>, <tt class="docutils literal"><span class="pre">--options-maybe=<pathname></span></tt>, and
<tt class="docutils literal"><span class="pre">--optlib-dir=[+]<directory></span></tt> are for loading optlib files you need
occasionally. See "Option File Options" section of ctags(1) for
these options.</p>
<p>As explained in "FILES" section of ctags(1), options for defining a
parser listed line by line in an optlib file. Prefixed white spaces are
ignored. A line starting with '#' is treated as a comment. Escaping
shell meta character is not needed.</p>
<p>Use <tt class="docutils literal">.ctags</tt> as file extension for optlib file. You can define
multiple parsers in an optlib file but it is better to make a file for
each parser definition.</p>
<p><tt class="docutils literal"><span class="pre">--_echo=<msg></span></tt> and <tt class="docutils literal"><span class="pre">--_force-quit=<num></span></tt> options are for debugging
optlib parser.</p>
</div>
<div class="section" id="overview-for-defining-a-parser">
<h2>Overview for defining a parser</h2>
<ol class="arabic">
<li><p class="first">Design the parser</p>
<p>You need know both the target language and the ctags'
concepts (definition, reference, kind, role, field, extra). About
the concepts, ctags(1) of Universal Ctags may help you.</p>
</li>
<li><p class="first">Give a name to the parser</p>
<p>Use <tt class="docutils literal"><span class="pre">--langdef=<name></span></tt> option. <em><name></em> is referred as <em><LANG></em> in
the later steps.</p>
</li>
<li><p class="first">Give a file pattern or file extension for activating the parser</p>
<p>Use <tt class="docutils literal"><span class="pre">--map-<LANG>=[+|-]<extension>|<pattern></span></tt>.</p>
</li>
<li><p class="first">Define kinds</p>
<p>Use <tt class="docutils literal"><span class="pre">--kinddef-<LANG>=<letter>,<name>,<description></span></tt> option.
Universal Ctags introduces this option. Exuberant Ctags doesn't
have. In Exuberant Ctags, a kind is defined as a side effect of
specifying <tt class="docutils literal"><span class="pre">--regex-<LANG>=</span></tt> option. So user doesn't have a
chance to recognize how important the definition of kind.</p>
</li>
<li><p class="first">Define patterns</p>
<p>Use <tt class="docutils literal"><span class="pre">--regex-<LANG>=/<line_pattern>/<name_pattern>/<kind-spec>/[<flags>]</span></tt>
option for a single-line regular expression. You can also use
<tt class="docutils literal"><span class="pre">--mline-regex-<LANG>=/<line_pattern>/<name_pattern>/<kind-spec>/[<flags>]</span></tt>
option for a multi-line regular expression.</p>
<p>As <em><kind-spec></em>, you can use the one-letter flag defined with
<tt class="docutils literal"><span class="pre">--kinddef-<LANG>=<letter>,<name>,<description></span></tt> option.</p>
</li>
</ol>
</div>
</div>
<div class="section" id="options">
<h1>OPTIONS</h1>
<dl class="docutils">
<dt><tt class="docutils literal"><span class="pre">--langdef=<name></span></tt></dt>
<dd><p class="first">Defines a new user-defined language, <em><name></em>, to be parsed with regular
expressions. Once defined, <em><name></em> may be used in other options taking
language names.</p>
<p><em><name></em> must consist of alphanumeric characters, '<tt class="docutils literal">#</tt>', or '<tt class="docutils literal">+</tt>'
('[a-zA-Z0-9#+]+'). The graph characters other than '<tt class="docutils literal">#</tt>' and
'<tt class="docutils literal">+</tt>' are disallowed (or reserved). Some of them (<tt class="docutils literal"><span class="pre">[-=:{.]</span></tt>) are
disallowed because they can make the command line parser of
ctags confused. The rest of them are just
reserved for future extending ctags.</p>
<p><tt class="docutils literal">all</tt> is an exception. <tt class="docutils literal">all</tt> as <em><name></em> is not acceptable. It is
a reserved word. See the description of
<tt class="docutils literal"><span class="pre">--kinds-(<LANG>|all)=[+|-](<kinds>|*)</span></tt> option in ctags(1) about how the
reserved word is used.</p>
<p class="last">The names of built-in parsers are capitalized. When
ctags evaluates an option in a command line, and
chooses a parser, ctags uses the names of
parsers in a case-insensitive way. Therefore, giving a name
started from a lowercase character doesn't help you to avoid the
parser name confliction. However, in a tags file,
ctags prints parser names in a case-sensitive
way; it prints a parser name as specified in <tt class="docutils literal"><span class="pre">--langdef=<name></span></tt>
option. Therefore, we recommend you to give a name started from a
lowercase character to your private optlib parser. With this
convention, people can know where a tag entry in a tag file comes
from a built-in parser or a private optlib parser.</p>
</dd>
<dt><tt class="docutils literal"><span class="pre">--kinddef-<LANG>=<letter>,<name>,<description></span></tt></dt>
<dd><p class="first">Define a kind for <em><LANG></em>.
Be not confused this with <tt class="docutils literal"><span class="pre">--kinds-<LANG></span></tt>.</p>
<p><em><letter></em> must be an alphabetical character ('[a-zA-EG-Z]')
other than "F". "F" has been reserved for representing a file
since Exuberant Ctags.</p>
<p><em><name></em> must start with an alphabetic character, and the rest
must be alphanumeric ('[a-zA-Z][a-zA-Z0-9]*'). Do not use
"file" as <em><name></em>. It has been reserved for representing a file
since Exuberant Ctags.</p>
<p>Note that using a number character in a <em><name></em> violates the
version 2 of tags file format though ctags
accepts it. For more detail, see tags(5).</p>
<p><em><description></em> comes from any printable ASCII characters. The
exception is <tt class="docutils literal">{</tt> and <tt class="docutils literal">\</tt>. <tt class="docutils literal">{</tt> is reserved for adding flags
this option in the future. So put <tt class="docutils literal">\</tt> before <tt class="docutils literal">{</tt> to include
<tt class="docutils literal">{</tt> to a description. To include <tt class="docutils literal">\</tt> itself to a description,
put <tt class="docutils literal">\</tt> before <tt class="docutils literal">\</tt>.</p>
<p>Both <em><letter></em>, <em><name></em> and their combination must be unique in
a <em><LANG></em>.</p>
<p>This option is newly introduced in Universal Ctags. This option
reduces the typing defining a regex pattern with
<tt class="docutils literal"><span class="pre">--regex-<LANG>=</span></tt>, and keeps the consistency of kind
definitions in a language.</p>
<p>The <em><letter></em> can be used as an argument for <tt class="docutils literal"><span class="pre">--kinds-<LANG></span></tt>
option to enable or disable the kind. Unless <tt class="docutils literal">K</tt> field is
enabled, the <em><letter></em> is used as value in the "kind" extension
field in tags output.</p>
<p>The <em><name></em> surrounded by braces can be used as an argument for
<tt class="docutils literal"><span class="pre">--kind-<LANG></span></tt> option. If <tt class="docutils literal">K</tt> field is enabled, the <em><name></em>
is used as value in the "kind" extension field in tags output.</p>
<p class="last">The <em><description></em> and <em><letter></em> are listed in <tt class="docutils literal"><span class="pre">--list-kinds</span></tt>
output. All three elements of the kind-spec are listed in
<tt class="docutils literal"><span class="pre">--list-kinds-full</span></tt> output. Don't use braces in the
<em><description></em>. They will be used meta characters in the future.</p>
</dd>
<dt><tt class="docutils literal"><span class="pre">--regex-<LANG>=/<line_pattern>/<name_pattern>/<kind-spec>/[<flags>]</span></tt></dt>
<dd><p class="first">Define a single-line regular expression.</p>
<p>The <em>/<line_pattern>/<name_pattern>/</em> pair defines a regular expression
replacement pattern, similar in style to <tt class="docutils literal">sed</tt> substitution
commands, <tt class="docutils literal">s/regexp/replacement/</tt>, with which to generate tags from source files mapped to
the named language, <em><LANG></em>, (case-insensitive; either a built-in
or user-defined language).</p>
<p>The regular expression, <em><line_pattern></em>, defines
an extended regular expression (roughly that used by egrep(1)),
which is used to locate a single source line containing a tag and
may specify tab characters using <tt class="docutils literal">\t</tt>.</p>
<p>When a matching line is
found, a tag will be generated for the name defined by
<em><name_pattern></em>, which generally will contain the special
back-references <tt class="docutils literal">\1</tt> through <tt class="docutils literal">\9</tt> to refer to matching sub-expression
groups within <em><line_pattern></em>.</p>
<p>The '<tt class="docutils literal">/</tt>' separator characters shown in the
parameter to the option can actually be replaced by any
character. Note that whichever separator character is used will
have to be escaped with a backslash ('<tt class="docutils literal">\</tt>') character wherever it is
used in the parameter as something other than a separator. The
regular expression defined by this option is added to the current
list of regular expressions for the specified language unless the
parameter is omitted, in which case the current list is cleared.</p>
<p>Unless modified by <em><flags></em>, <em><line_pattern></em> is interpreted as a POSIX
extended regular expression. The <em><name_pattern></em> should expand for all
matching lines to a non-empty string of characters, or a warning
message will be reported unless <tt class="docutils literal">{placeholder}</tt> regex flag is
specified.</p>
<p>A kind specifier (<em><kind-spec></em>) for tags matching regexp may
follow <em><name_pattern></em>, which will determine what kind of tag is
reported in the <tt class="docutils literal">kind</tt> extension field (see tags(5)).</p>
<p><em><kind-spec></em> has two forms: <em>one-letter form</em> and <em>full form</em>.</p>
<p>The one-letter form in the form of <tt class="docutils literal"><letter></tt>. It just refers a kind
<em><letter></em> defined with <tt class="docutils literal"><span class="pre">--kinddef-<LANG></span></tt>. This form is recommended in
Universal Ctags.</p>
<p>The full form of <em><kind-spec></em> is in the form of
<tt class="docutils literal"><span class="pre"><letter>,<name>,<description></span></tt>. Either the kind <em><name></em> and/or the
<em><description></em> can be omitted. See the description of
<tt class="docutils literal"><span class="pre">--kinddef-<LANG>=<letter>,<name>,<description></span></tt> option about the
elements.</p>
<p>The full form is supported only for keeping the compatibility with Exuberant
Ctags which does not have <tt class="docutils literal"><span class="pre">--kinddef-<LANG></span></tt> option. Supporting the
form will be removed from Universal Ctags in the future.</p>
<!-- MEMO: the following line is commented out
If *<kind-spec>* is omitted, it defaults to ``r,regex``. -->
<p>About <em><flags></em>, see "FLAGS FOR <tt class="docutils literal"><span class="pre">--regex-<LANG></span></tt> OPTION".</p>
<p class="last">For more information on the regular expressions used by
ctags, see either the regex(5,7) man page, or
the GNU info documentation for regex (e.g. "<tt class="docutils literal">info regex</tt>").</p>
</dd>
<dt><tt class="docutils literal"><span class="pre">--list-regex-flags</span></tt></dt>
<dd>Lists the flags that can be used in <tt class="docutils literal"><span class="pre">--regex-<LANG></span></tt> option.</dd>
<dt><tt class="docutils literal"><span class="pre">--list-mline-regex-flags</span></tt></dt>
<dd>Lists the flags that can be used in <tt class="docutils literal"><span class="pre">--mline-regex-<LANG></span></tt> option.</dd>
<dt><tt class="docutils literal"><span class="pre">--mline-regex-<LANG>=/<line_pattern>/<name_pattern>/<kind-spec>/[<flags>]</span></tt></dt>
<dd><p class="first">Define a multi-line regular expression.</p>
<p class="last">This option is similar to <tt class="docutils literal"><span class="pre">--regex-<LANG></span></tt> option except the pattern is
applied to the whole file’s contents, not line by line.</p>
</dd>
<dt><tt class="docutils literal"><span class="pre">--_echo=<message></span></tt></dt>
<dd>Print <em><message></em> to the standard error stream. This is helpful to
understand (and debug) optlib loading feature of Universal Ctags.</dd>
<dt><tt class="docutils literal"><span class="pre">--_force-quit[=<num>]</span></tt></dt>
<dd>Exits immediately when this option is processed. If <em><num></em> is used
as exit status. The default is 0. This is helpful to debug optlib
loading feature of Universal Ctags.</dd>
</dl>
<div class="section" id="flags-for-regex-lang-option">
<h2>FLAGS FOR <tt class="docutils literal"><span class="pre">--regex-<LANG></span></tt> OPTION</h2>
<p>You can specify more than one flag, <tt class="docutils literal"><span class="pre"><letter>|{<name>}</span></tt>, at the end of <tt class="docutils literal"><span class="pre">--regex-<LANG></span></tt> to
control how Universal Ctags uses the pattern.</p>
<p>Exuberant Ctags uses a <em><letter></em> to represent a flag. In
Universal Ctags, a <em><name></em> surrounded by braces (name form) can be used
in addition to <em><letter></em>. The name form makes a user reading an optlib
file easier.</p>
<p>The most of all flags newly added in Universal Ctags
don't have the one-letter representation. All of them have only the name
representation. <tt class="docutils literal"><span class="pre">--list-regex-flags</span></tt> lists all the flags.</p>
<dl class="docutils">
<dt><tt class="docutils literal">basic</tt> (one-letter form <tt class="docutils literal">b</tt>)</dt>
<dd>The pattern is interpreted as a POSIX basic regular expression.</dd>
<dt><tt class="docutils literal">exclusive</tt> (one-letter form <tt class="docutils literal">x</tt>)</dt>
<dd>Skip testing the other patterns if a line is matched to this
pattern. This is useful to avoid using CPU to parse line comments.</dd>
<dt><tt class="docutils literal">extend</tt> (one-letter form <tt class="docutils literal">e</tt>)</dt>
<dd>The pattern is interpreted as a POSIX extended regular
expression (default).</dd>
<dt><tt class="docutils literal">icase</tt> (one-letter form <tt class="docutils literal">i</tt>)</dt>
<dd>The regular expression is to be applied in a case-insensitive
manner.</dd>
<dt><tt class="docutils literal">placeholder</tt></dt>
<dd>Don't emit a tag captured with a regex pattern. The replacement
can be an empty string. See the following description of
<tt class="docutils literal"><span class="pre">scope=...</span></tt> flag about how this is useful.</dd>
</dl>
<p><tt class="docutils literal"><span class="pre">scope=(ref|push|pop|clear|set)</span></tt></p>
<blockquote>
<p>Specify what to do with the internal scope stack.</p>
<p>A parser programmed with <tt class="docutils literal"><span class="pre">--regex-<LANG></span></tt> has a stack (scope
stack) internally. You can use it for tracking scope
information. The <tt class="docutils literal"><span class="pre">scope=...</span></tt> flag is for manipulating and
utilizing the scope stack.</p>
<p>If <tt class="docutils literal">{scope=push}</tt> is specified, a tag captured with
<tt class="docutils literal"><span class="pre">--regex-<LANG></span></tt> is pushed to the stack. <tt class="docutils literal">{scope=push}</tt>
implies <tt class="docutils literal">{scope=ref}</tt>.</p>
<p>You can fill the scope field of captured tag with
<tt class="docutils literal">{scope=ref}</tt>. If <tt class="docutils literal">{scope=ref}</tt> flag is given,
ctags attaches the tag at the top to the tag
captured with <tt class="docutils literal"><span class="pre">--regex-<LANG></span></tt> as the value for the <tt class="docutils literal">scope:</tt>
field.</p>
<p>ctags pops the tag at the top of the stack when
<tt class="docutils literal"><span class="pre">--regex-<LANG></span></tt> with <tt class="docutils literal">{scope=pop}</tt> is matched to the input
line.</p>
<p>Specifying <tt class="docutils literal">{scope=clear}</tt> removes all the tags in the scope.
Specifying <tt class="docutils literal">{scope=set}</tt> removes all the tags in the scope, and
then pushes the captured tag as <tt class="docutils literal">{scope=push}</tt> does.</p>
<p>In some cases, you may want to use <tt class="docutils literal"><span class="pre">--regex-<LANG></span></tt> only for its
side effects: using it only to manipulate the stack but not for
capturing a tag. In such a case, make <em><name_pattern></em> component of
<tt class="docutils literal"><span class="pre">--regex-<LANG></span></tt> option empty while specifying <tt class="docutils literal">{placeholder}</tt>
as a regex flag. For example, a non-named tag can be put on
the stack by giving a regex flag "<tt class="docutils literal"><span class="pre">{scope=push}{placeholder}</span></tt>".</p>
<p>You may wonder what happens if a regex pattern with
<tt class="docutils literal">{scope=ref}</tt> flag matches an input line but the stack is empty,
or a non-named tag is at the top. If the regex pattern contains a
<tt class="docutils literal">{scope=ref}</tt> flag and the stack is empty, the <tt class="docutils literal">{scope=ref}</tt>
flag is ignored and nothing is attached to the <tt class="docutils literal">scope:</tt> field.</p>
<p>If the top of the stack contains an unnamed tag,
ctags searches deeper into the stack to find the
top-most named tag. If it reaches the bottom of the stack without
finding a named tag, the <tt class="docutils literal">{scope=ref}</tt> flag is ignored and
nothing is attached to the <tt class="docutils literal">scope:</tt> field.</p>
<p>When a named tag on the stack is popped or cleared as the side
effect of a pattern matching, ctags attaches the
line number of the match to the <tt class="docutils literal">end:</tt> field of
the named tag.</p>
<p>ctags clears all of the tags on the stack when it
reaches the end of the input source file. The line number of the
end is attached to the <tt class="docutils literal">end:</tt> field of the cleared tags.</p>
</blockquote>
<dl class="docutils">
<dt><tt class="docutils literal"><span class="pre">warning=<message></span></tt></dt>
<dd>print the given <em><message></em> at WARNING level</dd>
<dt><tt class="docutils literal"><span class="pre">fatal=<message></span></tt></dt>
<dd>print the given <em><message></em> and exit</dd>
</dl>
</div>
</div>
<div class="section" id="examples">
<h1>EXAMPLES</h1>
<div class="section" id="perl-pod">
<h2>Perl Pod</h2>
<p>This is the definition (pod.ctags) used in ctags for parsing Pod
(<a class="reference external" href="https://perldoc.perl.org/perlpod.html">https://perldoc.perl.org/perlpod.html</a>) file.</p>
<div class="system-message">
<p class="system-message-title">System Message: WARNING/2 (<tt class="docutils">ctags-optlib.7.rst</tt>, line 395)</p>
<p>Cannot analyze code. No Pygments lexer found for "ctags".</p>
<pre class="literal-block">
.. code-block:: ctags
--langdef=pod
--map-pod=+.pod
--kinddef-pod=c,chapter,chapters
--kinddef-pod=s,section,sections
--kinddef-pod=S,subsection,subsections
--kinddef-pod=t,subsubsection,subsubsections
--regex-pod=/^=head1[ \t]+(.+)/\1/c/
--regex-pod=/^=head2[ \t]+(.+)/\1/s/
--regex-pod=/^=head3[ \t]+(.+)/\1/S/
--regex-pod=/^=head4[ \t]+(.+)/\1/t/
</pre>
</div>
</div>
<div class="section" id="using-scope-regex-flags">
<h2>Using scope regex flags</h2>
<p>Let's think about writing a parser for a very small subset of the Ruby
language.</p>
<p>input source file (<tt class="docutils literal">input.srb</tt>):</p>
<pre class="literal-block">
class Example
def methodA
puts "in class_method"
end
def methodB
puts "in class_method"
end
end
</pre>
<p>The parser for the input should capture <tt class="docutils literal">Example</tt> with <tt class="docutils literal">class</tt> kind,
<tt class="docutils literal">methodA</tt>, and <tt class="docutils literal">methodB</tt> with <tt class="docutils literal">method</tt> kind. <tt class="docutils literal">methodA</tt> and <tt class="docutils literal">methodB</tt>
should have <tt class="docutils literal">Example</tt> as their scope. <tt class="docutils literal">end:</tt> fields of each tag
should have proper values.</p>
<p>optlib file (<tt class="docutils literal"><span class="pre">sub-ruby.ctags</span></tt>):</p>
<div class="system-message">
<p class="system-message-title">System Message: WARNING/2 (<tt class="docutils">ctags-optlib.7.rst</tt>, line 434)</p>
<p>Cannot analyze code. No Pygments lexer found for "ctags".</p>
<pre class="literal-block">
.. code-block:: ctags
--langdef=subRuby
--map-subRuby=.srb
--kinddef-subRuby=c,class,classes
--kinddef-subRuby=m,method,methods
--regex-subRuby=/^class[ \t]+([a-zA-Z][a-zA-Z0-9]+)/\1/c/{scope=push}
--regex-subRuby=/^end///{scope=pop}{placeholder}
--regex-subRuby=/^[ \t]+def[ \t]+([a-zA-Z][a-zA-Z0-9_]+)/\1/m/{scope=push}
--regex-subRuby=/^[ \t]+end///{scope=pop}{placeholder}
</pre>
</div>
<p>command line and output:</p>
<pre class="literal-block">
$ ctags --quiet --fields=+eK \
--options=./sub-ruby.ctags -o - input.srb
Example input.srb /^class Example$/;" class end:8
methodA input.srb /^ def methodA$/;" method class:Example end:4
methodB input.srb /^ def methodB$/;" method class:Example end:7
</pre>
</div>
</div>
<div class="section" id="see-also">
<h1>SEE ALSO</h1>
<p>The official Universal Ctags web site at:</p>
<p><a class="reference external" href="https://ctags.io/">https://ctags.io/</a></p>
<p>ctags(1), tags(5), regex(3), regex(7), egrep(1)</p>
</div>
<div class="section" id="author">
<h1>AUTHOR</h1>
<p>Universal Ctags project
<a class="reference external" href="https://ctags.io/">https://ctags.io/</a>
(This man page partially derived from ctags(1) of
Executable-ctags)</p>
<p>Darren Hiebert <<a class="reference external" href="mailto:dhiebert@users.sourceforge.net">dhiebert@users.sourceforge.net</a>>
<a class="reference external" href="http://DarrenHiebert.com/">http://DarrenHiebert.com/</a></p>
</div>
</div>
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