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Struct `std.format.spec.FormatSpec`

A general handler for format strings.


						
				struct FormatSpec(Char)
				

				  
				

				if (is(Unqual!Char == Char));

This handler centers around the function writeUpToNextSpec, which parses the format string until the next format specifier is found. After the call, it provides information about this format specifier in its numerous variables.

Constructors

Name	Description
`this` (fmt)	Creates a new `FormatSpec`.

Fields

Name	Type	Description
`dynamicSeparatorChar`	`bool`	The separator charactar is supplied at runtime.
`flDash`	`bool`	The format specifier contained a `'-'`.
`flEqual`	`bool`	The format specifier contained a `'='`.
`flHash`	`bool`	The format specifier contained a `'#'`.
`flPlus`	`bool`	The format specifier contained a `'+'`.
`flSeparator`	`bool`	The format specifier contained a `','`.
`flSpace`	`bool`	The format specifier contained a space.
`flZero`	`bool`	The format specifier contained a `'0'`.
`indexEnd`	`ubyte`	Index of the last argument for positional parameter ranges.
`indexStart`	`ubyte`	Index of the argument for positional parameters.
`nested`	`const(Char)[]`	The inner format string of a nested format specifier.
`precision`	`int`	Precision. Its semantic depends on the format character.
`sep`	`const(Char)[]`	The separator of a nested format specifier.
`separatorChar`	`dchar`	Character to use as separator.
`separators`	`int`	Number of elements between separators.
`spec`	`char`	The format character.
`trailing`	`const(Char)[]`	Contains the part of the format string, that has not yet been parsed.
`width`	`int`	Minimum width.

Methods

Name	Description
`separatorCharPos` ()	Set to `DYNAMIC` when the separator character is supplied at runtime.
`toString` ()	Provides a string representation.
`toString` (writer)	Writes a string representation to an output range.
`writeUpToNextSpec` (writer)	Writes the format string to an output range until the next format specifier is found and parse that format specifier.

Parameters

Name	Description
Char	the character type of the format string

Example

import std.array : appender;

auto a = appender!(string)();
auto fmt = "Number: %6.4e\nString: %s";
auto f = FormatSpec!char(fmt);

writeln(f.writeUpToNextSpec(a)); // true

writeln(a.data); // "Number: "
writeln(f.trailing); // "\nString: %s"
writeln(f.spec); // 'e'
writeln(f.width); // 6
writeln(f.precision); // 4

writeln(f.writeUpToNextSpec(a)); // true

writeln(a.data); // "Number: \nString: "
writeln(f.trailing); // ""
writeln(f.spec); // 's'

writeln(f.writeUpToNextSpec(a)); // false

writeln(a.data); // "Number: \nString: "

Authors

Walter Bright, Andrei Alexandrescu, and Kenji Hara

License

Boost License 1.0.