6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-10-02 21:17:17 +00:00
Code Issues Projects Releases Wiki Activity

Sprinkle code examples and command-line interaction examples with some style

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@20557 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Misha Brukman
2005-03-11 00:00:33 +00:00
parent fc1a27b2a5
commit f75c4b444b
1 changed files with 96 additions and 94 deletions
Download Patch File Download Diff File Expand all files Collapse all files

190
docs/CommandLine.html
View File

@@ -192,19 +192,19 @@ can do.</p>
<p>To start out, you need to include the CommandLine header file into your <p>To start out, you need to include the CommandLine header file into your
program:</p> program:</p>
<pre> <div class="doc_code"><pre>
#include "Support/CommandLine.h" #include "Support/CommandLine.h"
</pre> </pre></div>
<p>Additionally, you need to add this as the first line of your main <p>Additionally, you need to add this as the first line of your main
program:</p> program:</p>
<pre> <div class="doc_code"><pre>
int main(int argc, char **argv) { int main(int argc, char **argv) {
<a href="#cl::ParseCommandLineOptions">cl::ParseCommandLineOptions</a>(argc, argv); <a href="#cl::ParseCommandLineOptions">cl::ParseCommandLineOptions</a>(argc, argv);
... ...
} }
</pre> </pre></div>
<p>... which actually parses the arguments and fills in the variable <p>... which actually parses the arguments and fills in the variable
declarations.</p> declarations.</p>
@@ -220,9 +220,9 @@ to specify where to put the output. With the CommandLine library, this is
represented like this:</p> represented like this:</p>
<a name="value_desc_example"></a> <a name="value_desc_example"></a>
<pre> <div class="doc_code"><pre>
<a href="#cl::opt">cl::opt</a>&lt;string&gt; OutputFilename("<i>o</i>", <a href="#cl::desc">cl::desc</a>("<i>Specify output filename</i>"), <a href="#cl::value_desc">cl::value_desc</a>("<i>filename</i>")); <a href="#cl::opt">cl::opt</a>&lt;string&gt; OutputFilename("<i>o</i>", <a href="#cl::desc">cl::desc</a>("<i>Specify output filename</i>"), <a href="#cl::value_desc">cl::value_desc</a>("<i>filename</i>"));
</pre> </pre></div>
<p>This declares a global variable "<tt>OutputFilename</tt>" that is used to <p>This declares a global variable "<tt>OutputFilename</tt>" that is used to
capture the result of the "<tt>o</tt>" argument (first parameter). We specify capture the result of the "<tt>o</tt>" argument (first parameter). We specify
@@ -235,25 +235,25 @@ that the data type that we are parsing is a string.</p>
to output for the "<tt>--help</tt>" option. In this case, we get a line that to output for the "<tt>--help</tt>" option. In this case, we get a line that
looks like this:</p> looks like this:</p>
<pre> <div class="doc_code"><pre>
USAGE: compiler [options] USAGE: compiler [options]
OPTIONS: OPTIONS:
-help - display available options (--help-hidden for more) -help - display available options (--help-hidden for more)
<b>-o &lt;filename&gt; - Specify output filename</b> <b>-o &lt;filename&gt; - Specify output filename</b>
</pre> </pre></div>
<p>Because we specified that the command line option should parse using the <p>Because we specified that the command line option should parse using the
<tt>string</tt> data type, the variable declared is automatically usable as a <tt>string</tt> data type, the variable declared is automatically usable as a
real string in all contexts that a normal C++ string object may be used. For real string in all contexts that a normal C++ string object may be used. For
example:</p> example:</p>
<pre> <div class="doc_code"><pre>
... ...
ofstream Output(OutputFilename.c_str()); ofstream Output(OutputFilename.c_str());
if (Out.good()) ... if (Out.good()) ...
... ...
</pre> </pre></div>
<p>There are many different options that you can use to customize the command <p>There are many different options that you can use to customize the command
line option handling library, but the above example shows the general interface line option handling library, but the above example shows the general interface
@@ -270,9 +270,9 @@ href="#positional">positional</a> arguments to be specified for the program.
These positional arguments are filled with command line parameters that are not These positional arguments are filled with command line parameters that are not
in option form. We use this feature like this:</p> in option form. We use this feature like this:</p>
<pre> <div class="doc_code"><pre>
<a href="#cl::opt">cl::opt</a>&lt;string&gt; InputFilename(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;input file&gt;</i>"), <a href="#cl::init">cl::init</a>("<i>-</i>")); <a href="#cl::opt">cl::opt</a>&lt;string&gt; InputFilename(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;input file&gt;</i>"), <a href="#cl::init">cl::init</a>("<i>-</i>"));
</pre> </pre></div>
<p>This declaration indicates that the first positional argument should be <p>This declaration indicates that the first positional argument should be
treated as the input filename. Here we use the <tt><a treated as the input filename. Here we use the <tt><a
@@ -285,16 +285,16 @@ that the user always specify an input filename, we would add the <tt><a
href="#cl::Required">cl::Required</a></tt> flag, and we could eliminate the href="#cl::Required">cl::Required</a></tt> flag, and we could eliminate the
<tt><a href="#cl::init">cl::init</a></tt> modifier, like this:</p> <tt><a href="#cl::init">cl::init</a></tt> modifier, like this:</p>
<pre> <div class="doc_code"><pre>
<a href="#cl::opt">cl::opt</a>&lt;string&gt; InputFilename(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;input file&gt;</i>"), <b><a href="#cl::Required">cl::Required</a></b>); <a href="#cl::opt">cl::opt</a>&lt;string&gt; InputFilename(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;input file&gt;</i>"), <b><a href="#cl::Required">cl::Required</a></b>);
</pre> </pre></div>
<p>Again, the CommandLine library does not require the options to be specified <p>Again, the CommandLine library does not require the options to be specified
in any particular order, so the above declaration is equivalent to:</p> in any particular order, so the above declaration is equivalent to:</p>
<pre> <div class="doc_code"><pre>
<a href="#cl::opt">cl::opt</a>&lt;string&gt; InputFilename(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::Required">cl::Required</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;input file&gt;</i>")); <a href="#cl::opt">cl::opt</a>&lt;string&gt; InputFilename(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::Required">cl::Required</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;input file&gt;</i>"));
</pre> </pre></div>
<p>By simply adding the <tt><a href="#cl::Required">cl::Required</a></tt> flag, <p>By simply adding the <tt><a href="#cl::Required">cl::Required</a></tt> flag,
the CommandLine library will automatically issue an error if the argument is not the CommandLine library will automatically issue an error if the argument is not
@@ -304,13 +304,13 @@ can alter the default behaviour of the library, on a per-option basis. By
adding one of the declarations above, the <tt>--help</tt> option synopsis is now adding one of the declarations above, the <tt>--help</tt> option synopsis is now
extended to:</p> extended to:</p>
<pre> <div class="doc_code"><pre>
USAGE: compiler [options] <b>&lt;input file&gt;</b> USAGE: compiler [options] <b>&lt;input file&gt;</b>
OPTIONS: OPTIONS:
-help - display available options (--help-hidden for more) -help - display available options (--help-hidden for more)
-o &lt;filename&gt; - Specify output filename -o &lt;filename&gt; - Specify output filename
</pre> </pre></div>
<p>... indicating that an input filename is expected.</p> <p>... indicating that an input filename is expected.</p>
@@ -329,11 +329,11 @@ file, "<tt>--quiet</tt>" to enable quiet mode, and "<tt>-q</tt>" for backwards
compatibility with some of our users. We can support these by declaring options compatibility with some of our users. We can support these by declaring options
of boolean type like this:</p> of boolean type like this:</p>
<pre> <div class="doc_code"><pre>
<a href="#cl::opt">cl::opt</a>&lt;bool&gt; Force ("<i>f</i>", <a href="#cl::desc">cl::desc</a>("<i>Overwrite output files</i>")); <a href="#cl::opt">cl::opt</a>&lt;bool&gt; Force ("<i>f</i>", <a href="#cl::desc">cl::desc</a>("<i>Overwrite output files</i>"));
<a href="#cl::opt">cl::opt</a>&lt;bool&gt; Quiet ("<i>quiet</i>", <a href="#cl::desc">cl::desc</a>("<i>Don't print informational messages</i>")); <a href="#cl::opt">cl::opt</a>&lt;bool&gt; Quiet ("<i>quiet</i>", <a href="#cl::desc">cl::desc</a>("<i>Don't print informational messages</i>"));
<a href="#cl::opt">cl::opt</a>&lt;bool&gt; Quiet2("<i>q</i>", <a href="#cl::desc">cl::desc</a>("<i>Don't print informational messages</i>"), <a href="#cl::Hidden">cl::Hidden</a>); <a href="#cl::opt">cl::opt</a>&lt;bool&gt; Quiet2("<i>q</i>", <a href="#cl::desc">cl::desc</a>("<i>Don't print informational messages</i>"), <a href="#cl::Hidden">cl::Hidden</a>);
</pre> </pre></div>
<p>This does what you would expect: it declares three boolean variables <p>This does what you would expect: it declares three boolean variables
("<tt>Force</tt>", "<tt>Quiet</tt>", and "<tt>Quiet2</tt>") to recognize these ("<tt>Force</tt>", "<tt>Quiet</tt>", and "<tt>Quiet2</tt>") to recognize these
@@ -351,12 +351,12 @@ it assigns the value of true to the variable), or it allows the values
"<tt>true</tt>" or "<tt>false</tt>" to be specified, allowing any of the "<tt>true</tt>" or "<tt>false</tt>" to be specified, allowing any of the
following inputs:</p> following inputs:</p>
<pre> <div class="doc_code"><pre>
compiler -f # No value, 'Force' == true compiler -f # No value, 'Force' == true
compiler -f=true # Value specified, 'Force' == true compiler -f=true # Value specified, 'Force' == true
compiler -f=TRUE # Value specified, 'Force' == true compiler -f=TRUE # Value specified, 'Force' == true
compiler -f=FALSE # Value specified, 'Force' == false compiler -f=FALSE # Value specified, 'Force' == false
</pre> </pre></div>
<p>... you get the idea. The <a href="#boolparser">bool parser</a> just turns <p>... you get the idea. The <a href="#boolparser">bool parser</a> just turns
the string values into boolean values, and rejects things like '<tt>compiler the string values into boolean values, and rejects things like '<tt>compiler
@@ -367,7 +367,7 @@ library calls to parse the string value into the specified data type.</p>
<p>With the declarations above, "<tt>compiler --help</tt>" emits this:</p> <p>With the declarations above, "<tt>compiler --help</tt>" emits this:</p>
<pre> <div class="doc_code"><pre>
USAGE: compiler [options] &lt;input file&gt; USAGE: compiler [options] &lt;input file&gt;
OPTIONS: OPTIONS:
@@ -375,11 +375,11 @@ OPTIONS:
-o - Override output filename -o - Override output filename
<b>-quiet - Don't print informational messages</b> <b>-quiet - Don't print informational messages</b>
-help - display available options (--help-hidden for more) -help - display available options (--help-hidden for more)
</pre> </pre></div>
<p>and "<tt>opt --help-hidden</tt>" prints this:</p> <p>and "<tt>opt --help-hidden</tt>" prints this:</p>
<pre> <div class="doc_code"><pre>
USAGE: compiler [options] &lt;input file&gt; USAGE: compiler [options] &lt;input file&gt;
OPTIONS: OPTIONS:
@@ -388,7 +388,7 @@ OPTIONS:
<b>-q - Don't print informational messages</b> <b>-q - Don't print informational messages</b>
-quiet - Don't print informational messages -quiet - Don't print informational messages
-help - display available options (--help-hidden for more) -help - display available options (--help-hidden for more)
</pre> </pre></div>
<p>This brief example has shown you how to use the '<tt><a <p>This brief example has shown you how to use the '<tt><a
href="#cl::opt">cl::opt</a></tt>' class to parse simple scalar command line href="#cl::opt">cl::opt</a></tt>' class to parse simple scalar command line
@@ -408,22 +408,22 @@ and <a href="#list">lists</a> of options.</p>
<p>So far, the example works well, except for the fact that we need to check the <p>So far, the example works well, except for the fact that we need to check the
quiet condition like this now:</p> quiet condition like this now:</p>
<pre> <div class="doc_code"><pre>
... ...
if (!Quiet &amp;&amp; !Quiet2) printInformationalMessage(...); if (!Quiet &amp;&amp; !Quiet2) printInformationalMessage(...);
... ...
</pre> </pre></div>
<p>... which is a real pain! Instead of defining two values for the same <p>... which is a real pain! Instead of defining two values for the same
condition, we can use the "<tt><a href="#cl::alias">cl::alias</a></tt>" class to make the "<tt>-q</tt>" condition, we can use the "<tt><a href="#cl::alias">cl::alias</a></tt>" class to make the "<tt>-q</tt>"
option an <b>alias</b> for the "<tt>-quiet</tt>" option, instead of providing option an <b>alias</b> for the "<tt>-quiet</tt>" option, instead of providing
a value itself:</p> a value itself:</p>
<pre> <div class="doc_code"><pre>
<a href="#cl::opt">cl::opt</a>&lt;bool&gt; Force ("<i>f</i>", <a href="#cl::desc">cl::desc</a>("<i>Overwrite output files</i>")); <a href="#cl::opt">cl::opt</a>&lt;bool&gt; Force ("<i>f</i>", <a href="#cl::desc">cl::desc</a>("<i>Overwrite output files</i>"));
<a href="#cl::opt">cl::opt</a>&lt;bool&gt; Quiet ("<i>quiet</i>", <a href="#cl::desc">cl::desc</a>("<i>Don't print informational messages</i>")); <a href="#cl::opt">cl::opt</a>&lt;bool&gt; Quiet ("<i>quiet</i>", <a href="#cl::desc">cl::desc</a>("<i>Don't print informational messages</i>"));
<a href="#cl::alias">cl::alias</a> QuietA("<i>q</i>", <a href="#cl::desc">cl::desc</a>("<i>Alias for -quiet</i>"), <a href="#cl::aliasopt">cl::aliasopt</a>(Quiet)); <a href="#cl::alias">cl::alias</a> QuietA("<i>q</i>", <a href="#cl::desc">cl::desc</a>("<i>Alias for -quiet</i>"), <a href="#cl::aliasopt">cl::aliasopt</a>(Quiet));
</pre> </pre></div>
<p>The third line (which is the only one we modified from above) defines a <p>The third line (which is the only one we modified from above) defines a
"<tt>-q</tt> alias that updates the "<tt>Quiet</tt>" variable (as specified by "<tt>-q</tt> alias that updates the "<tt>Quiet</tt>" variable (as specified by
@@ -436,11 +436,11 @@ output</tt>).</p>
<p>Now the application code can simply use:</p> <p>Now the application code can simply use:</p>
<pre> <div class="doc_code"><pre>
... ...
if (!Quiet) printInformationalMessage(...); if (!Quiet) printInformationalMessage(...);
... ...
</pre> </pre></div>
<p>... which is much nicer! The "<tt><a href="#cl::alias">cl::alias</a></tt>" <p>... which is much nicer! The "<tt><a href="#cl::alias">cl::alias</a></tt>"
can be used to specify an alternative name for any variable type, and has many can be used to specify an alternative name for any variable type, and has many
@@ -486,7 +486,7 @@ see if some level &gt;= "<tt>-O1</tt>" is enabled.</li>
CommandLine library fill it in with the appropriate level directly, which is CommandLine library fill it in with the appropriate level directly, which is
used like this:</p> used like this:</p>
<pre> <div class="doc_code"><pre>
enum OptLevel { enum OptLevel {
g, O1, O2, O3 g, O1, O2, O3
}; };
@@ -502,7 +502,7 @@ enum OptLevel {
... ...
if (OptimizationLevel &gt;= O2) doPartialRedundancyElimination(...); if (OptimizationLevel &gt;= O2) doPartialRedundancyElimination(...);
... ...
</pre> </pre></div>
<p>This declaration defines a variable "<tt>OptimizationLevel</tt>" of the <p>This declaration defines a variable "<tt>OptimizationLevel</tt>" of the
"<tt>OptLevel</tt>" enum type. This variable can be assigned any of the values "<tt>OptLevel</tt>" enum type. This variable can be assigned any of the values
@@ -514,7 +514,7 @@ enum values can be specified. The "<tt>clEnumVal</tt>" macros ensure that the
command line arguments matched the enum values. With this option added, our command line arguments matched the enum values. With this option added, our
help output now is:</p> help output now is:</p>
<pre> <div class="doc_code"><pre>
USAGE: compiler [options] &lt;input file&gt; USAGE: compiler [options] &lt;input file&gt;
OPTIONS: OPTIONS:
@@ -527,14 +527,14 @@ OPTIONS:
-help - display available options (--help-hidden for more) -help - display available options (--help-hidden for more)
-o &lt;filename&gt; - Specify output filename -o &lt;filename&gt; - Specify output filename
-quiet - Don't print informational messages -quiet - Don't print informational messages
</pre> </pre></div>
<p>In this case, it is sort of awkward that flag names correspond directly to <p>In this case, it is sort of awkward that flag names correspond directly to
enum names, because we probably don't want a enum definition named "<tt>g</tt>" enum names, because we probably don't want a enum definition named "<tt>g</tt>"
in our program. Because of this, we can alternatively write this example like in our program. Because of this, we can alternatively write this example like
this:</p> this:</p>
<pre> <div class="doc_code"><pre>
enum OptLevel { enum OptLevel {
Debug, O1, O2, O3 Debug, O1, O2, O3
}; };
@@ -550,7 +550,7 @@ enum OptLevel {
... ...
if (OptimizationLevel == Debug) outputDebugInfo(...); if (OptimizationLevel == Debug) outputDebugInfo(...);
... ...
</pre> </pre></div>
<p>By using the "<tt>clEnumValN</tt>" macro instead of "<tt>clEnumVal</tt>", we <p>By using the "<tt>clEnumValN</tt>" macro instead of "<tt>clEnumVal</tt>", we
can directly specify the name that the flag should get. In general a direct can directly specify the name that the flag should get. In general a direct
@@ -575,7 +575,7 @@ following options, of which only one can be specified at a time:
our optimization level flags, but we also specify an option name. For this our optimization level flags, but we also specify an option name. For this
case, the code looks like this:</p> case, the code looks like this:</p>
<pre> <div class="doc_code"><pre>
enum DebugLev { enum DebugLev {
nodebuginfo, quick, detailed nodebuginfo, quick, detailed
}; };
@@ -587,14 +587,14 @@ enum DebugLev {
clEnumVal(quick, "<i>enable quick debug information</i>"), clEnumVal(quick, "<i>enable quick debug information</i>"),
clEnumVal(detailed, "<i>enable detailed debug information</i>"), clEnumVal(detailed, "<i>enable detailed debug information</i>"),
clEnumValEnd)); clEnumValEnd));
</pre> </pre></div>
<p>This definition defines an enumerated command line variable of type "<tt>enum <p>This definition defines an enumerated command line variable of type "<tt>enum
DebugLev</tt>", which works exactly the same way as before. The difference here DebugLev</tt>", which works exactly the same way as before. The difference here
is just the interface exposed to the user of your program and the help output by is just the interface exposed to the user of your program and the help output by
the "<tt>--help</tt>" option:</p> the "<tt>--help</tt>" option:</p>
<pre> <div class="doc_code"><pre>
USAGE: compiler [options] &lt;input file&gt; USAGE: compiler [options] &lt;input file&gt;
OPTIONS: OPTIONS:
@@ -611,7 +611,7 @@ OPTIONS:
-help - display available options (--help-hidden for more) -help - display available options (--help-hidden for more)
-o &lt;filename&gt; - Specify output filename -o &lt;filename&gt; - Specify output filename
-quiet - Don't print informational messages -quiet - Don't print informational messages
</pre> </pre></div>
<p>Again, the only structural difference between the debug level declaration and <p>Again, the only structural difference between the debug level declaration and
the optimization level declaration is that the debug level declaration includes the optimization level declaration is that the debug level declaration includes
@@ -637,16 +637,16 @@ important. This is what the "<tt><a href="#cl::list">cl::list</a></tt>"
template is for. First, start by defining an enum of the optimizations that you template is for. First, start by defining an enum of the optimizations that you
would like to perform:</p> would like to perform:</p>
<pre> <div class="doc_code"><pre>
enum Opts { enum Opts {
// 'inline' is a C++ keyword, so name it 'inlining' // 'inline' is a C++ keyword, so name it 'inlining'
dce, constprop, inlining, strip dce, constprop, inlining, strip
}; };
</pre> </pre></div>
<p>Then define your "<tt><a href="#cl::list">cl::list</a></tt>" variable:</p> <p>Then define your "<tt><a href="#cl::list">cl::list</a></tt>" variable:</p>
<pre> <div class="doc_code"><pre>
<a href="#cl::list">cl::list</a>&lt;Opts&gt; OptimizationList(<a href="#cl::desc">cl::desc</a>("<i>Available Optimizations:</i>"), <a href="#cl::list">cl::list</a>&lt;Opts&gt; OptimizationList(<a href="#cl::desc">cl::desc</a>("<i>Available Optimizations:</i>"),
<a href="#cl::values">cl::values</a>( <a href="#cl::values">cl::values</a>(
clEnumVal(dce , "<i>Dead Code Elimination</i>"), clEnumVal(dce , "<i>Dead Code Elimination</i>"),
@@ -654,17 +654,17 @@ enum Opts {
clEnumValN(inlining, "<i>inline</i>", "<i>Procedure Integration</i>"), clEnumValN(inlining, "<i>inline</i>", "<i>Procedure Integration</i>"),
clEnumVal(strip , "<i>Strip Symbols</i>"), clEnumVal(strip , "<i>Strip Symbols</i>"),
clEnumValEnd)); clEnumValEnd));
</pre> </pre></div>
<p>This defines a variable that is conceptually of the type <p>This defines a variable that is conceptually of the type
"<tt>std::vector&lt;enum Opts&gt;</tt>". Thus, you can access it with standard "<tt>std::vector&lt;enum Opts&gt;</tt>". Thus, you can access it with standard
vector methods:</p> vector methods:</p>
<pre> <div class="doc_code"><pre>
for (unsigned i = 0; i != OptimizationList.size(); ++i) for (unsigned i = 0; i != OptimizationList.size(); ++i)
switch (OptimizationList[i]) switch (OptimizationList[i])
... ...
</pre> </pre></div>
<p>... to iterate through the list of options specified.</p> <p>... to iterate through the list of options specified.</p>
@@ -676,11 +676,11 @@ arguments together if there may be more than one specified. In the case of a
linker, for example, the linker takes several '<tt>.o</tt>' files, and needs to linker, for example, the linker takes several '<tt>.o</tt>' files, and needs to
capture them into a list. This is naturally specified as:</p> capture them into a list. This is naturally specified as:</p>
<pre> <div class="doc_code"><pre>
... ...
<a href="#cl::list">cl::list</a>&lt;std::string&gt; InputFilenames(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("&lt;Input files&gt;"), <a href="#cl::OneOrMore">cl::OneOrMore</a>); <a href="#cl::list">cl::list</a>&lt;std::string&gt; InputFilenames(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("&lt;Input files&gt;"), <a href="#cl::OneOrMore">cl::OneOrMore</a>);
... ...
</pre> </pre></div>
<p>This variable works just like a "<tt>vector&lt;string&gt;</tt>" object. As <p>This variable works just like a "<tt>vector&lt;string&gt;</tt>" object. As
such, accessing the list is simple, just like above. In this example, we used such, accessing the list is simple, just like above. In this example, we used
@@ -709,17 +709,17 @@ call in main. This additional argument is then printed as the overview
information for your program, allowing you to include any additional information information for your program, allowing you to include any additional information
that you want. For example:</p> that you want. For example:</p>
<pre> <div class="doc_code"><pre>
int main(int argc, char **argv) { int main(int argc, char **argv) {
<a href="#cl::ParseCommandLineOptions">cl::ParseCommandLineOptions</a>(argc, argv, " CommandLine compiler example\n\n" <a href="#cl::ParseCommandLineOptions">cl::ParseCommandLineOptions</a>(argc, argv, " CommandLine compiler example\n\n"
" This program blah blah blah...\n"); " This program blah blah blah...\n");
... ...
} }
</pre> </pre></div>
<p>Would yield the help output:</p> <p>would yield the help output:</p>
<pre> <div class="doc_code"><pre>
<b>OVERVIEW: CommandLine compiler example <b>OVERVIEW: CommandLine compiler example
This program blah blah blah...</b> This program blah blah blah...</b>
@@ -730,7 +730,7 @@ OPTIONS:
... ...
-help - display available options (--help-hidden for more) -help - display available options (--help-hidden for more)
-o &lt;filename&gt; - Specify output filename -o &lt;filename&gt; - Specify output filename
</pre> </pre></div>
</div> </div>
@@ -764,20 +764,20 @@ tool takes a regular expression argument, and an optional filename to search
through (which defaults to standard input if a filename is not specified). through (which defaults to standard input if a filename is not specified).
Using the CommandLine library, this would be specified as:</p> Using the CommandLine library, this would be specified as:</p>
<pre> <div class="doc_code"><pre>
<a href="#cl::opt">cl::opt</a>&lt;string&gt; Regex (<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;regular expression&gt;</i>"), <a href="#cl::Required">cl::Required</a>); <a href="#cl::opt">cl::opt</a>&lt;string&gt; Regex (<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;regular expression&gt;</i>"), <a href="#cl::Required">cl::Required</a>);
<a href="#cl::opt">cl::opt</a>&lt;string&gt; Filename(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;input file&gt;</i>"), <a href="#cl::init">cl::init</a>("<i>-</i>")); <a href="#cl::opt">cl::opt</a>&lt;string&gt; Filename(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;input file&gt;</i>"), <a href="#cl::init">cl::init</a>("<i>-</i>"));
</pre> </pre></div>
<p>Given these two option declarations, the <tt>--help</tt> output for our grep <p>Given these two option declarations, the <tt>--help</tt> output for our grep
replacement would look like this:</p> replacement would look like this:</p>
<pre> <div class="doc_code"><pre>
USAGE: spiffygrep [options] <b>&lt;regular expression&gt; &lt;input file&gt;</b> USAGE: spiffygrep [options] <b>&lt;regular expression&gt; &lt;input file&gt;</b>
OPTIONS: OPTIONS:
-help - display available options (--help-hidden for more) -help - display available options (--help-hidden for more)
</pre> </pre></div>
<p>... and the resultant program could be used just like the standard <p>... and the resultant program could be used just like the standard
<tt>grep</tt> tool.</p> <tt>grep</tt> tool.</p>
@@ -804,7 +804,7 @@ first, you will have trouble doing this, because it will try to find an argument
named '<tt>-foo</tt>', and will fail (and single quotes will not save you). named '<tt>-foo</tt>', and will fail (and single quotes will not save you).
Note that the system <tt>grep</tt> has the same problem:</p> Note that the system <tt>grep</tt> has the same problem:</p>
<pre> <div class="doc_code"><pre>
$ spiffygrep '-foo' test.txt $ spiffygrep '-foo' test.txt
Unknown command line argument '-foo'. Try: spiffygrep --help' Unknown command line argument '-foo'. Try: spiffygrep --help'
@@ -813,7 +813,7 @@ Note that the system <tt>grep</tt> has the same problem:</p>
grep: illegal option -- o grep: illegal option -- o
grep: illegal option -- o grep: illegal option -- o
Usage: grep -hblcnsviw pattern file . . . Usage: grep -hblcnsviw pattern file . . .
</pre> </pre></div>
<p>The solution for this problem is the same for both your tool and the system <p>The solution for this problem is the same for both your tool and the system
version: use the '<tt>--</tt>' marker. When the user specifies '<tt>--</tt>' on version: use the '<tt>--</tt>' marker. When the user specifies '<tt>--</tt>' on
@@ -821,10 +821,10 @@ the command line, it is telling the program that all options after the
'<tt>--</tt>' should be treated as positional arguments, not options. Thus, we '<tt>--</tt>' should be treated as positional arguments, not options. Thus, we
can use it like this:</p> can use it like this:</p>
<pre> <div class="doc_code"><pre>
$ spiffygrep -- -foo test.txt $ spiffygrep -- -foo test.txt
...output... ...output...
</pre> </pre></div>
</div> </div>
@@ -847,7 +847,9 @@ can use it like this:</p>
<tt>cl::list::getPosition(optnum)</tt> method. This method returns the <tt>cl::list::getPosition(optnum)</tt> method. This method returns the
absolute position (as found on the command line) of the <tt>optnum</tt> absolute position (as found on the command line) of the <tt>optnum</tt>
item in the <tt>cl::list</tt>.</p> item in the <tt>cl::list</tt>.</p>
<p>The idiom for usage is like this:<pre><tt> <p>The idiom for usage is like this:</p>
<div class="doc_code"><pre>
static cl::list&lt;std::string&gt; Files(cl::Positional, cl::OneOrMore); static cl::list&lt;std::string&gt; Files(cl::Positional, cl::OneOrMore);
static cl::listlt;std::string&gt; Libraries("l", cl::ZeroOrMore); static cl::listlt;std::string&gt; Libraries("l", cl::ZeroOrMore);
@@ -877,8 +879,8 @@ can use it like this:</p>
else else
break; // we're done with the list break; // we're done with the list
} }
} }</pre></div>
</tt></pre></p>
<p>Note that, for compatibility reasons, the <tt>cl::opt</tt> also supports an <p>Note that, for compatibility reasons, the <tt>cl::opt</tt> also supports an
<tt>unsigned getPosition()</tt> option that will provide the absolute position <tt>unsigned getPosition()</tt> option that will provide the absolute position
of that option. You can apply the same approach as above with a of that option. You can apply the same approach as above with a
@@ -906,23 +908,23 @@ arguments to the script. These arguments to the script are parsed by the bourne
shell command line option processor, but are not interpreted as options to the shell command line option processor, but are not interpreted as options to the
shell itself. Using the CommandLine library, we would specify this as:</p> shell itself. Using the CommandLine library, we would specify this as:</p>
<pre> <div class="doc_code"><pre>
<a href="#cl::opt">cl::opt</a>&lt;string&gt; Script(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;input script&gt;</i>"), <a href="#cl::init">cl::init</a>("-")); <a href="#cl::opt">cl::opt</a>&lt;string&gt; Script(<a href="#cl::Positional">cl::Positional</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;input script&gt;</i>"), <a href="#cl::init">cl::init</a>("-"));
<a href="#cl::list">cl::list</a>&lt;string&gt; Argv(<a href="#cl::ConsumeAfter">cl::ConsumeAfter</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;program arguments&gt;...</i>")); <a href="#cl::list">cl::list</a>&lt;string&gt; Argv(<a href="#cl::ConsumeAfter">cl::ConsumeAfter</a>, <a href="#cl::desc">cl::desc</a>("<i>&lt;program arguments&gt;...</i>"));
<a href="#cl::opt">cl::opt</a>&lt;bool&gt; Trace("<i>x</i>", <a href="#cl::desc">cl::desc</a>("<i>Enable trace output</i>")); <a href="#cl::opt">cl::opt</a>&lt;bool&gt; Trace("<i>x</i>", <a href="#cl::desc">cl::desc</a>("<i>Enable trace output</i>"));
</pre> </pre></div>
<p>which automatically provides the help output:</p> <p>which automatically provides the help output:</p>
<pre> <div class="doc_code"><pre>
USAGE: spiffysh [options] <b>&lt;input script&gt; &lt;program arguments&gt;...</b> USAGE: spiffysh [options] <b>&lt;input script&gt; &lt;program arguments&gt;...</b>
OPTIONS: OPTIONS:
-help - display available options (--help-hidden for more) -help - display available options (--help-hidden for more)
<b>-x - Enable trace output</b> <b>-x - Enable trace output</b>
</pre> </pre></div>
<p>At runtime, if we run our new shell replacement as '<tt>spiffysh -x test.sh <p>At runtime, if we run our new shell replacement as `<tt>spiffysh -x test.sh
-a -x -y bar</tt>', the <tt>Trace</tt> variable will be set to true, the -a -x -y bar</tt>', the <tt>Trace</tt> variable will be set to true, the
<tt>Script</tt> variable will be set to "<tt>test.sh</tt>", and the <tt>Script</tt> variable will be set to "<tt>test.sh</tt>", and the
<tt>Argv</tt> list will contain <tt>["-a", "-x", "-y", "bar"]</tt>, because they <tt>Argv</tt> list will contain <tt>["-a", "-x", "-y", "bar"]</tt>, because they
@@ -1308,7 +1310,7 @@ and they will still work as designed.</p>
input option into (potentially multiple) prefix and grouping options. The input option into (potentially multiple) prefix and grouping options. The
strategy basically looks like this:</p> strategy basically looks like this:</p>
<p><tt>parse(string OrigInput) {</tt> <div class="doc_code"><tt>parse(string OrigInput) {</tt>
<ol> <ol>
<li><tt>string input = OrigInput;</tt> <li><tt>string input = OrigInput;</tt>
@@ -1324,10 +1326,10 @@ strategy basically looks like this:</p>
&nbsp;&nbsp;while (!isOption(input) &amp;&amp; !input.empty()) input.pop_back();<br> &nbsp;&nbsp;while (!isOption(input) &amp;&amp; !input.empty()) input.pop_back();<br>
}</tt> }</tt>
<li><tt>if (!OrigInput.empty()) error();</tt></li> <li><tt>if (!OrigInput.empty()) error();</tt></li>
</ol> </ol>
<p><tt>}</tt></p> <p><tt>}</tt></p>
</div>
</div> </div>
@@ -1452,13 +1454,13 @@ options, and is the one used most of the time. It is a templated class which
can take up to three arguments (all except for the first have default values can take up to three arguments (all except for the first have default values
though):</p> though):</p>
<pre> <div class="doc_code"><pre>
<b>namespace</b> cl { <b>namespace</b> cl {
<b>template</b> &lt;<b>class</b> DataType, <b>bool</b> ExternalStorage = <b>false</b>, <b>template</b> &lt;<b>class</b> DataType, <b>bool</b> ExternalStorage = <b>false</b>,
<b>class</b> ParserClass = parser&lt;DataType&gt; &gt; <b>class</b> ParserClass = parser&lt;DataType&gt; &gt;
<b>class</b> opt; <b>class</b> opt;
} }
</pre> </pre></div>
<p>The first template argument specifies what underlying data type the command <p>The first template argument specifies what underlying data type the command
line argument is, and is used to select a default parser implementation. The line argument is, and is used to select a default parser implementation. The
@@ -1486,13 +1488,13 @@ href="#customparser">custom parser</a>.</p>
line options. It too is a templated class which can take up to three line options. It too is a templated class which can take up to three
arguments:</p> arguments:</p>
<pre> <div class="doc_code"><pre>
<b>namespace</b> cl { <b>namespace</b> cl {
<b>template</b> &lt;<b>class</b> DataType, <b>class</b> Storage = <b>bool</b>, <b>template</b> &lt;<b>class</b> DataType, <b>class</b> Storage = <b>bool</b>,
<b>class</b> ParserClass = parser&lt;DataType&gt; &gt; <b>class</b> ParserClass = parser&lt;DataType&gt; &gt;
<b>class</b> list; <b>class</b> list;
} }
</pre> </pre></div>
<p>This class works the exact same as the <a <p>This class works the exact same as the <a
href="#cl::opt"><tt>cl::opt</tt></a> class, except that the second argument is href="#cl::opt"><tt>cl::opt</tt></a> class, except that the second argument is
@@ -1512,11 +1514,11 @@ be used.</p>
<p>The <tt>cl::alias</tt> class is a nontemplated class that is used to form <p>The <tt>cl::alias</tt> class is a nontemplated class that is used to form
aliases for other arguments.</p> aliases for other arguments.</p>
<pre> <div class="doc_code"><pre>
<b>namespace</b> cl { <b>namespace</b> cl {
<b>class</b> alias; <b>class</b> alias;
} }
</pre> </pre></div>
<p>The <a href="#cl::aliasopt"><tt>cl::aliasopt</tt></a> attribute should be <p>The <a href="#cl::aliasopt"><tt>cl::aliasopt</tt></a> attribute should be
used to specify which option this is an alias for. Alias arguments default to used to specify which option this is an alias for. Alias arguments default to
@@ -1535,22 +1537,22 @@ the conversion from string to data.</p>
<p>The <tt>cl::extrahelp</tt> class is a nontemplated class that allows extra <p>The <tt>cl::extrahelp</tt> class is a nontemplated class that allows extra
help text to be printed out for the <tt>--help</tt> option.</p> help text to be printed out for the <tt>--help</tt> option.</p>
<pre> <div class="doc_code"><pre>
<b>namespace</b> cl { <b>namespace</b> cl {
<b>struct</b> extrahelp; <b>struct</b> extrahelp;
} }
</pre> </pre></div>
<p>To use the extrahelp, simply construct one with a <tt>const char*</tt> <p>To use the extrahelp, simply construct one with a <tt>const char*</tt>
parameter to the constructor. The text passed to the constructor will be printed parameter to the constructor. The text passed to the constructor will be printed
at the bottom of the help message, verbatim. Note that multiple at the bottom of the help message, verbatim. Note that multiple
<tt>cl::extrahelp</tt> <b>can</b> be used but this practice is discouraged. If <tt>cl::extrahelp</tt> <b>can</b> be used, but this practice is discouraged. If
your tool needs to print additional help information, put all that help into a your tool needs to print additional help information, put all that help into a
single <tt>cl::extrahelp</tt> instance.</p> single <tt>cl::extrahelp</tt> instance.</p>
<p>For example:</p> <p>For example:</p>
<pre> <div class="doc_code"><pre>
cl::extrahelp("\nADDITIONAL HELP:\n\n This is the extra help\n"); cl::extrahelp("\nADDITIONAL HELP:\n\n This is the extra help\n");
</pre> </pre></div>
</div> </div>
<!-- ======================================================================= --> <!-- ======================================================================= -->
@@ -1677,13 +1679,13 @@ this the default for all <tt>unsigned</tt> options.</p>
<p>To start out, we declare our new <tt>FileSizeParser</tt> class:</p> <p>To start out, we declare our new <tt>FileSizeParser</tt> class:</p>
<pre> <div class="doc_code"><pre>
<b>struct</b> FileSizeParser : <b>public</b> cl::basic_parser&lt;<b>unsigned</b>&gt; { <b>struct</b> FileSizeParser : <b>public</b> cl::basic_parser&lt;<b>unsigned</b>&gt; {
<i>// parse - Return true on error.</i> <i>// parse - Return true on error.</i>
<b>bool</b> parse(cl::Option &amp;O, <b>const char</b> *ArgName, <b>const</b> std::string &amp;ArgValue, <b>bool</b> parse(cl::Option &amp;O, <b>const char</b> *ArgName, <b>const</b> std::string &amp;ArgValue,
<b>unsigned</b> &amp;Val); <b>unsigned</b> &amp;Val);
}; };
</pre> </pre></div>
<p>Our new class inherits from the <tt>cl::basic_parser</tt> template class to <p>Our new class inherits from the <tt>cl::basic_parser</tt> template class to
fill in the default, boiler plate, code for us. We give it the data type that fill in the default, boiler plate, code for us. We give it the data type that
@@ -1699,7 +1701,7 @@ is not well formed, the parser should output an error message and return true.
Otherwise it should return false and set '<tt>Val</tt>' to the parsed value. In Otherwise it should return false and set '<tt>Val</tt>' to the parsed value. In
our example, we implement <tt>parse</tt> as:</p> our example, we implement <tt>parse</tt> as:</p>
<pre> <div class="doc_code"><pre>
<b>bool</b> FileSizeParser::parse(cl::Option &amp;O, <b>const char</b> *ArgName, <b>bool</b> FileSizeParser::parse(cl::Option &amp;O, <b>const char</b> *ArgName,
<b>const</b> std::string &amp;Arg, <b>unsigned</b> &amp;Val) { <b>const</b> std::string &amp;Arg, <b>unsigned</b> &amp;Val) {
<b>const char</b> *ArgStart = Arg.c_str(); <b>const char</b> *ArgStart = Arg.c_str();
@@ -1725,7 +1727,7 @@ our example, we implement <tt>parse</tt> as:</p>
} }
} }
} }
</pre> </pre></div>
<p>This function implements a very simple parser for the kinds of strings we are <p>This function implements a very simple parser for the kinds of strings we are
interested in. Although it has some holes (it allows "<tt>123KKK</tt>" for interested in. Although it has some holes (it allows "<tt>123KKK</tt>" for
@@ -1734,25 +1736,25 @@ itself to print out the error message (the <tt>error</tt> method always returns
true) in order to get a nice error message (shown below). Now that we have our true) in order to get a nice error message (shown below). Now that we have our
parser class, we can use it like this:</p> parser class, we can use it like this:</p>
<pre> <div class="doc_code"><pre>
<b>static</b> <a href="#cl::opt">cl::opt</a>&lt;<b>unsigned</b>, <b>false</b>, FileSizeParser&gt; <b>static</b> <a href="#cl::opt">cl::opt</a>&lt;<b>unsigned</b>, <b>false</b>, FileSizeParser&gt;
MFS(<i>"max-file-size"</i>, <a href="#cl::desc">cl::desc</a>(<i>"Maximum file size to accept"</i>), MFS(<i>"max-file-size"</i>, <a href="#cl::desc">cl::desc</a>(<i>"Maximum file size to accept"</i>),
<a href="#cl::value_desc">cl::value_desc</a>("<i>size</i>")); <a href="#cl::value_desc">cl::value_desc</a>("<i>size</i>"));
</pre> </pre></div>
<p>Which adds this to the output of our program:</p> <p>Which adds this to the output of our program:</p>
<pre> <div class="doc_code"><pre>
OPTIONS: OPTIONS:
-help - display available options (--help-hidden for more) -help - display available options (--help-hidden for more)
... ...
<b>-max-file-size=&lt;size&gt; - Maximum file size to accept</b> <b>-max-file-size=&lt;size&gt; - Maximum file size to accept</b>
</pre> </pre></div>
<p>And we can test that our parse works correctly now (the test program just <p>And we can test that our parse works correctly now (the test program just
prints out the max-file-size argument value):</p> prints out the max-file-size argument value):</p>
<pre> <div class="doc_code"><pre>
$ ./test $ ./test
MFS: 0 MFS: 0
$ ./test -max-file-size=123MB $ ./test -max-file-size=123MB
@@ -1761,7 +1763,7 @@ $ ./test -max-file-size=3G
MFS: 3221225472 MFS: 3221225472
$ ./test -max-file-size=dog $ ./test -max-file-size=dog
-max-file-size option: 'dog' value invalid for file size argument! -max-file-size option: 'dog' value invalid for file size argument!
</pre> </pre></div>
<p>It looks like it works. The error message that we get is nice and helpful, <p>It looks like it works. The error message that we get is nice and helpful,
and we seem to accept reasonable file sizes. This wraps up the "custom parser" and we seem to accept reasonable file sizes. This wraps up the "custom parser"