2007-11-06 12:13:52 +00:00
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< div class = "titlepage" >< div >< div >< h4 class = "title" >
< a name = "fusion.sequence.operator.i_o" ></ a >< a href = "i_o.html" title = "I/O" > I/O</ a ></ h4 ></ div ></ div ></ div >
< div class = "toc" >< dl >
< dt >< span class = "section" >< a href = "i_o/in.html" > in</ a ></ span ></ dt >
< dt >< span class = "section" >< a href = "i_o/out.html" > out</ a ></ span ></ dt >
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< p >
The I/O operators: < tt class = "computeroutput" >< span class = "special" > << </ span ></ tt >
and < tt class = "computeroutput" >< span class = "special" > >> </ span ></ tt > work generically
on all Fusion sequences. The global < tt class = "computeroutput" >< span class = "keyword" > operator</ span >< span class = "special" > << </ span ></ tt > has been overloaded for generic
output streams such that < a href = "../../sequence.html" title = "Sequence" > Sequence</ a > (s)
are output by recursively calling < tt class = "computeroutput" >< span class = "keyword" > operator</ span >< span class = "special" > << </ span ></ tt > for each element. Analogously,
the global < tt class = "computeroutput" >< span class = "keyword" > operator</ span >< span class = "special" > >> </ span ></ tt >
has been overloaded to extract < a href = "../../sequence.html" title = "Sequence" > Sequence</ a > (s)
from generic input streams by recursively calling < tt class = "computeroutput" >< span class = "keyword" > operator</ span >< span class = "special" > >> </ span ></ tt > for each element.
</ p >
< p >
The default delimiter between the elements is space, and the < a href = "../../sequence.html" title = "Sequence" > Sequence</ a >
is enclosed in parenthesis. For Example:
</ p >
< pre class = "programlisting" >
< a href = "../../container/vector.html" title = "vector" >< tt class = "computeroutput" >< span class = "identifier" > vector</ span ></ tt ></ a >< span class = "special" > < </ span >< span class = "keyword" > float</ span >< span class = "special" > ,</ span > < span class = "keyword" > int</ span >< span class = "special" > ,</ span > < span class = "identifier" > std</ span >< span class = "special" > ::</ span >< span class = "identifier" > string</ span >< span class = "special" > > </ span > < span class = "identifier" > a</ span >< span class = "special" > (</ span >< span class = "number" > 1.0f</ span >< span class = "special" > ,</ span > < span class = "number" > 2</ span >< span class = "special" > ,</ span > < span class = "identifier" > std</ span >< span class = "special" > ::</ span >< span class = "identifier" > string</ span >< span class = "special" > (</ span >< span class = "string" > "Howdy folks!"</ span >< span class = "special" > );</ span >
< span class = "identifier" > cout</ span > < span class = "special" > << </ span > < span class = "identifier" > a</ span >< span class = "special" > ;</ span >
</ pre >
< p >
outputs the < a href = "../../container/vector.html" title = "vector" >< tt class = "computeroutput" >< span class = "identifier" > vector</ span ></ tt ></ a >
as: (1.0 2 Howdy folks!)
</ p >
< p >
The library defines three manipulators for changing the default behavior:
</ p >
< div class = "variablelist" >
< p class = "title" >< b > Manipulators</ b ></ p >
< dl >
< dt >< span class = "term" >< tt class = "computeroutput" >< span class = "identifier" > tuple_open</ span >< span class = "special" > (</ span >< span class = "identifier" > arg</ span >< span class = "special" > )</ span ></ tt ></ span ></ dt >
< dd >< p >
Defines the character that is output before the first element.
</ p ></ dd >
< dt >< span class = "term" >< tt class = "computeroutput" >< span class = "identifier" > tuple_close</ span >< span class = "special" > (</ span >< span class = "identifier" > arg</ span >< span class = "special" > )</ span ></ tt ></ span ></ dt >
< dd >< p >
Defines the character that is output after the last element.
</ p ></ dd >
< dt >< span class = "term" >< tt class = "computeroutput" >< span class = "identifier" > tuple_delimiter</ span >< span class = "special" > (</ span >< span class = "identifier" > arg</ span >< span class = "special" > )</ span ></ tt ></ span ></ dt >
< dd >< p >
Defines the delimiter character between elements.
</ p ></ dd >
</ dl >
</ div >
< p >
The argument to < tt class = "computeroutput" >< span class = "identifier" > tuple_open</ span ></ tt > ,
< tt class = "computeroutput" >< span class = "identifier" > tuple_close</ span ></ tt > and < tt class = "computeroutput" >< span class = "identifier" > tuple_delimiter</ span ></ tt > may be a < tt class = "computeroutput" >< span class = "keyword" > char</ span ></ tt > , < tt class = "computeroutput" >< span class = "keyword" > wchar_t</ span ></ tt > ,
a C-string, or a wide C-string.
</ p >
< p >
Example:
</ p >
< pre class = "programlisting" >
< span class = "identifier" > std</ span >< span class = "special" > ::</ span >< span class = "identifier" > cout</ span > < span class = "special" > << </ span > < span class = "identifier" > tuple_open</ span >< span class = "special" > (</ span >< span class = "char" > '['</ span >< span class = "special" > )</ span > < span class = "special" > << </ span > < span class = "identifier" > tuple_close</ span >< span class = "special" > (</ span >< span class = "char" > ']'</ span >< span class = "special" > )</ span > < span class = "special" > << </ span > < span class = "identifier" > tuple_delimiter</ span >< span class = "special" > (</ span >< span class = "string" > ", "</ span >< span class = "special" > )</ span > < span class = "special" > << </ span > < span class = "identifier" > a</ span >< span class = "special" > ;</ span >
</ pre >
< p >
outputs the same < a href = "../../container/vector.html" title = "vector" >< tt class = "computeroutput" >< span class = "identifier" > vector</ span ></ tt ></ a > , < tt class = "computeroutput" >< span class = "identifier" > a</ span ></ tt >
as: [1.0, 2, Howdy folks!]
</ p >
< p >
The same manipulators work with < tt class = "computeroutput" >< span class = "keyword" > operator</ span >< span class = "special" > >> </ span ></ tt > and < tt class = "computeroutput" >< span class = "identifier" > istream</ span ></ tt >
as well. Suppose the < tt class = "computeroutput" >< span class = "identifier" > std</ span >< span class = "special" > ::</ span >< span class = "identifier" > cin</ span ></ tt >
stream contains the following data:
</ p >
< pre class = "programlisting" >
< span class = "special" > (</ span >< span class = "number" > 1</ span > < span class = "number" > 2</ span > < span class = "number" > 3</ span >< span class = "special" > )</ span > < span class = "special" > [</ span >< span class = "number" > 4</ span >< span class = "special" > :</ span >< span class = "number" > 5</ span >< span class = "special" > ]</ span >
</ pre >
< p >
The code:
</ p >
< pre class = "programlisting" >
< a href = "../../container/vector.html" title = "vector" >< tt class = "computeroutput" >< span class = "identifier" > vector</ span ></ tt ></ a >< span class = "special" > < </ span >< span class = "keyword" > int</ span >< span class = "special" > ,</ span > < span class = "keyword" > int</ span >< span class = "special" > ,</ span > < span class = "keyword" > int</ span >< span class = "special" > > </ span > < span class = "identifier" > i</ span >< span class = "special" > ;</ span >
< a href = "../../container/vector.html" title = "vector" >< tt class = "computeroutput" >< span class = "identifier" > vector</ span ></ tt ></ a >< span class = "special" > < </ span >< span class = "keyword" > int</ span >< span class = "special" > ,</ span > < span class = "keyword" > int</ span >< span class = "special" > > </ span > < span class = "identifier" > j</ span >< span class = "special" > ;</ span >
< span class = "identifier" > std</ span >< span class = "special" > ::</ span >< span class = "identifier" > cin</ span > < span class = "special" > >> </ span > < span class = "identifier" > i</ span >< span class = "special" > ;</ span >
< span class = "identifier" > std</ span >< span class = "special" > ::</ span >< span class = "identifier" > cin</ span > < span class = "special" > >> </ span > < span class = "identifier" > set_open</ span >< span class = "special" > (</ span >< span class = "char" > '['</ span >< span class = "special" > )</ span > < span class = "special" > >> </ span > < span class = "identifier" > set_close</ span >< span class = "special" > (</ span >< span class = "char" > ']'</ span >< span class = "special" > )</ span > < span class = "special" > >> </ span > < span class = "identifier" > set_delimiter</ span >< span class = "special" > (</ span >< span class = "char" > ':'</ span >< span class = "special" > );</ span >
< span class = "identifier" > std</ span >< span class = "special" > ::</ span >< span class = "identifier" > cin</ span > < span class = "special" > >> </ span > < span class = "identifier" > j</ span >< span class = "special" > ;</ span >
</ pre >
< p >
reads the data into the < a href = "../../container/vector.html" title = "vector" >< tt class = "computeroutput" >< span class = "identifier" > vector</ span ></ tt ></ a > (s) < tt class = "computeroutput" >< span class = "identifier" > i</ span ></ tt >
and < tt class = "computeroutput" >< span class = "identifier" > j</ span ></ tt > .
</ p >
< p >
Note that extracting < a href = "../../sequence.html" title = "Sequence" > Sequence</ a > (s)
with < tt class = "computeroutput" >< span class = "identifier" > std</ span >< span class = "special" > ::</ span >< span class = "identifier" > string</ span ></ tt > or C-style string elements does
not generally work, since the streamed < a href = "../../sequence.html" title = "Sequence" > Sequence</ a >
representation may not be unambiguously parseable.
</ p >
< a name = "fusion.sequence.operator.i_o.header" ></ a >< h5 >
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< a name = "id519768" ></ a >
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< a href = "i_o.html#fusion.sequence.operator.i_o.header" > Header</ a >
</ h5 >
< pre class = "programlisting" >
< span class = "preprocessor" > #include</ span > < span class = "special" > < </ span >< span class = "identifier" > boost</ span >< span class = "special" > /</ span >< span class = "identifier" > fusion</ span >< span class = "special" > /</ span >< span class = "identifier" > sequence</ span >< span class = "special" > /</ span >< span class = "identifier" > io</ span >< span class = "special" > .</ span >< span class = "identifier" > hpp</ span >< span class = "special" > > </ span >
< span class = "preprocessor" > #include</ span > < span class = "special" > < </ span >< span class = "identifier" > boost</ span >< span class = "special" > /</ span >< span class = "identifier" > fusion</ span >< span class = "special" > /</ span >< span class = "identifier" > include</ span >< span class = "special" > /</ span >< span class = "identifier" > io</ span >< span class = "special" > .</ span >< span class = "identifier" > hpp</ span >< span class = "special" > > </ span >
</ pre >
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2007-11-16 08:03:15 +00:00
< td align = "right" >< div class = "copyright-footer" > Copyright © 2001-2007 Joel de Guzman, Dan Marsden, Tobias
2007-11-07 16:22:38 +00:00
Schwinger< p >
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at < a href = "http://www.boost.org/LICENSE_1_0.txt" target = "_top" > http://www.boost.org/LICENSE_1_0.txt</ a > )
2007-11-16 08:03:15 +00:00
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2007-11-06 12:13:52 +00:00
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