std:: regex_replace
|
Defined in header
<regex>
|
||
|
template
<
class
OutputIt,
class
BidirIt,
class
Traits,
class
CharT,
class
STraits,
class
SAlloc
>
|
(1) | (since C++11) |
|
template
<
class
OutputIt,
class
BidirIt,
class
Traits,
class
CharT
>
OutputIt regex_replace
(
OutputIt out, BidirIt first, BidirIt last,
|
(2) | (since C++11) |
|
template
<
class
Traits,
class
CharT,
class
STraits,
class
SAlloc,
class
FTraits,
class
FAlloc
>
|
(3) | (since C++11) |
|
template
<
class
Traits,
class
CharT,
class
STraits,
class
SAlloc
>
std::
basic_string
<
CharT, STraits, SAlloc
>
|
(4) | (since C++11) |
|
template
<
class
Traits,
class
CharT,
class
STraits,
class
SAlloc
>
std::
basic_string
<
CharT
>
|
(5) | (since C++11) |
|
template
<
class
Traits,
class
CharT
>
std::
basic_string
<
CharT
>
|
(6) | (since C++11) |
regex_replace
uses the regular expression
re
to perform substitution on the target character sequence:
[
first
,
last
)
to
out
, replacing any sequences that match
re
with characters formatted by
fmt
. Equivalent to:
using iter_type = std::regex_iterator<BidirIt, CharT, Traits>; iter_type seq_begin(first, last, re, flags), seq_end; using result_type = std::match_results<BidirIt>; result_type m; bool need_to_copy = (flags & std::regex_constants::format_no_copy) == 0; bool format_all = (flags & std::regex_constants::format_first_only) != 0; for (iter_type i = seq_begin; i != seq.end(); ++i) { m = *i; if (need_to_copy) out = std::copy(m.prefix().first, m.prefix().second, out); if (format_all || i == seq_begin) out = /* replace-expr */ } if (need_to_copy) out = m.ready() ? std::copy(m.suffix().first, m.suffix().second, out) : std::copy(first, last, out); return out;
regex_replace ( std:: back_inserter ( result ) ,
str. begin ( ) , str. end ( ) , re, fmt, flags ) ;
return result ; .
regex_replace ( std:: back_inserter ( result ) ,
s, s + std:: char_traits < CharT > :: length ( s ) , re, fmt, flags ) ;
return result ; .
Parameters
| first, last | - | the target character range |
| str | - | the target std::string |
| s | - | the target null-terminated C-style string |
| re | - | the regular expression |
| fmt | - | the regex replacement format string, exact syntax depends on the value of flags |
| flags | - | flags used to determine how the match will be performed |
| out | - | output iterator to store the result of the replacement |
Return value
As described above.
Exceptions
May throw std::regex_error to indicate an error condition .
Example
#include <iostream> #include <iterator> #include <regex> #include <string> int main() { std::string text = "Quick brown fox"; std::regex vowel_re("a|e|i|o|u"); // write the results to an output iterator std::regex_replace(std::ostreambuf_iterator<char>(std::cout), text.begin(), text.end(), vowel_re, "*"); // construct a string holding the results std::cout << '\n' << std::regex_replace(text, vowel_re, "[$&]") << '\n'; }
Output:
Q**ck br*wn f*x Q[u][i]ck br[o]wn f[o]x
Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior |
|---|---|---|---|
| LWG 2213 | C++11 | out was not updated by the replacements | out is updated |
See also
|
(C++11)
|
attempts to match a regular expression to any part of a character sequence
(function template) |
|
(C++11)
|
options specific to matching
(typedef) |
|
replaces specified portion of a string
(public member function of
std::basic_string<CharT,Traits,Allocator>
)
|