std::setfill
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setfill
(C++20)(C++20)
(C++14)
Defined in header
<iomanip>
template< class CharT >
/*unspecified*/ setfill( CharT c );
/*unspecified*/ setfill( CharT c );
When used in an expression out << setfill(c) sets the fill character of the stream out to c.
[edit] Parameters
c
-
new value for the fill character
[edit] Return value
An object of unspecified type such that
- if out is an object of type std::basic_ostream <CharT, Traits>, the expression out << setfill(c)
- has type std::basic_ostream <CharT, Traits>&
- has value out
- behaves as if it called f(out, c)
where the function f is defined as:
template<class CharT, class Traits> void f(std::basic_ios <CharT, Traits>& str, CharT c) { // set fill character str.fill(c); }
[edit] Notes
The current fill character may be obtained with std::ostream::fill .
[edit] Example
Run this code
Output:
default fill: [ 42]
setfill('*'): [********42][edit] 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 183 | C++98 | setbase could only be used withstreams of type std::ostream |
usable with any output character stream |