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<h1 class='fqn'><span class='in-band'><a href='index.html'>nom</a>::<wbr><a class='macro' href=''>map_opt!</a></span><span class='out-of-band'><span id='render-detail'>
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</span><a id='src-7389' class='srclink' href='../src/nom/macros.rs.html#343-366' title='goto source code'>[src]</a></span></h1>
<pre class='rust macro'>
<span class='macro'>macro_rules</span><span class='macro'>!</span> <span class='ident'>map_opt</span>(
(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>i</span>:<span class='ident'>expr</span>, <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>submac</span>:<span class='macro'>ident</span><span class='macro'>!</span>( $(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>args</span>:<span class='ident'>tt</span>)<span class='op'>*</span> ), <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>submac2</span>:<span class='macro'>ident</span><span class='macro'>!</span>( $(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>args2</span>:<span class='ident'>tt</span>)<span class='op'>*</span> )) <span class='op'>=></span> (
{
<span class='kw'>match</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>submac</span><span class='op'>!</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>i</span>, $(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>args</span>)<span class='op'>*</span>) {
<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>IResult</span>::<span class='ident'>Error</span>(<span class='ident'>e</span>) <span class='op'>=></span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>IResult</span>::<span class='ident'>Error</span>(<span class='ident'>e</span>),
<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>IResult</span>::<span class='ident'>Incomplete</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>Needed</span>::<span class='ident'>Unknown</span>) <span class='op'>=></span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>IResult</span>::<span class='ident'>Incomplete</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>Needed</span>::<span class='ident'>Unknown</span>),
<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>IResult</span>::<span class='ident'>Incomplete</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>Needed</span>::<span class='ident'>Size</span>(<span class='ident'>i</span>)) <span class='op'>=></span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>IResult</span>::<span class='ident'>Incomplete</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>Needed</span>::<span class='ident'>Size</span>(<span class='ident'>i</span>)),
<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>IResult</span>::<span class='ident'>Done</span>(<span class='ident'>i</span>, <span class='ident'>o</span>) <span class='op'>=></span> <span class='kw'>match</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>submac2</span><span class='op'>!</span>(<span class='ident'>o</span>, $(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>args2</span>)<span class='op'>*</span>) {
<span class='prelude-val'>Some</span>(<span class='ident'>output</span>) <span class='op'>=></span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>IResult</span>::<span class='ident'>Done</span>(<span class='ident'>i</span>, <span class='ident'>output</span>),
<span class='prelude-val'>None</span> <span class='op'>=></span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>IResult</span>::<span class='ident'>Error</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='prelude-val'>Err</span>::<span class='ident'>Position</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>crate</span>::<span class='ident'>ErrorCode</span>::<span class='ident'>MapOpt</span> <span class='kw'>as</span> <span class='ident'>u32</span>, <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>i</span>))
}
}
}
);
(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>i</span>:<span class='ident'>expr</span>, <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>submac</span>:<span class='macro'>ident</span><span class='macro'>!</span>( $(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>args</span>:<span class='ident'>tt</span>)<span class='op'>*</span> ), <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>g</span>:<span class='ident'>expr</span>) <span class='op'>=></span> (
<span class='macro'>map_opt</span><span class='macro'>!</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>i</span>, <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>submac</span><span class='op'>!</span>($(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>args</span>)<span class='op'>*</span>), <span class='macro'>call</span><span class='macro'>!</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>g</span>));
);
(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>i</span>:<span class='ident'>expr</span>, <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>f</span>:<span class='ident'>expr</span>, <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>g</span>:<span class='ident'>expr</span>) <span class='op'>=></span> (
<span class='macro'>map_opt</span><span class='macro'>!</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>i</span>, <span class='macro'>call</span><span class='macro'>!</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>f</span>), <span class='macro'>call</span><span class='macro'>!</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>g</span>));
);
(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>i</span>:<span class='ident'>expr</span>, <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>f</span>:<span class='ident'>expr</span>, <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>submac</span>:<span class='macro'>ident</span><span class='macro'>!</span>( $(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>args</span>:<span class='ident'>tt</span>)<span class='op'>*</span> )) <span class='op'>=></span> (
<span class='macro'>map_opt</span><span class='macro'>!</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>i</span>, <span class='macro'>call</span><span class='macro'>!</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>f</span>), <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>submac</span><span class='op'>!</span>($(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>args</span>)<span class='op'>*</span>));
);
);
</pre>
<div class='docblock'><p>maps a function returning an Option on the output of a parser</p>
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