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std.outbuffer

Serialize data to ubyte arrays.
Authors:

Source std/outbuffer.d

class OutBuffer;
OutBuffer provides a way to build up an array of bytes out of raw data. It is useful for things like preparing an array of bytes to write out to a file. OutBuffer's byte order is the format native to the computer. To control the byte order (endianness), use a class derived from OutBuffer. OutBuffer's internal buffer is allocated with the GC. Pointers stored into the buffer are scanned by the GC, but you have to ensure proper alignment, e.g. by using alignSize((void*).sizeof).
Examples:
import std.string : cmp;

OutBuffer buf = new OutBuffer();

writeln(buf.offset); // 0
buf.write("hello");
buf.write(cast(byte) 0x20);
buf.write("world");
buf.printf(" %d", 62665);
writeln(cmp(buf.toString(), "hello world 62665")); // 0

buf.clear();
writeln(cmp(buf.toString(), "")); // 0
buf.write("New data");
writeln(cmp(buf.toString(), "New data")); // 0
inout pure nothrow scope @safe inout(ubyte)[] toBytes();
Convert to array of bytes.
pure nothrow @trusted void reserve(size_t nbytes);
Preallocate nbytes more to the size of the internal buffer.
This is a speed optimization, a good guess at the maximum size of the resulting buffer will improve performance by eliminating reallocations and copying.
alias put = write;
put enables OutBuffer to be used as an OutputRange.
pure nothrow @safe void write(scope const(ubyte)[] bytes);

pure nothrow @safe void write(byte b);

pure nothrow @safe void write(char c);

pure nothrow @safe void write(dchar c);

pure nothrow @safe void write(short s);

pure nothrow @safe void write(int i);

pure nothrow @safe void write(long l);
Append data to the internal buffer.
pure nothrow @safe void fill(size_t nbytes, ubyte val = 0);
Append nbytes of val to the internal buffer.
Parameters:
size_t nbytes Number of bytes to fill.
ubyte val Value to fill, defaults to 0.
pure nothrow @safe void fill0(size_t nbytes);
Append nbytes of 0 to the internal buffer.

Param nbytes - number of bytes to fill.

pure nothrow @safe void alignSize(size_t alignsize, ubyte val = 0);
Append bytes until the buffer aligns on a power of 2 boundary.
By default fills with 0 bytes.
Parameters:
size_t alignsize Alignment value. Must be power of 2.
ubyte val Value to fill, defaults to 0.
Examples:
OutBuffer buf = new OutBuffer();
buf.write(cast(ubyte) 1);
buf.align2();
writeln(buf.toBytes()); // "\x01\x00"
buf.write(cast(ubyte) 2);
buf.align4();
writeln(buf.toBytes()); // "\x01\x00\x02\x00"
buf.write(cast(ubyte) 3);
buf.alignSize(8);
writeln(buf.toBytes()); // "\x01\x00\x02\x00\x03\x00\x00\x00"
Examples:
ditto
OutBuffer buf = new OutBuffer();
buf.write(cast(ubyte) 1);
buf.align2(0x55);
writeln(buf.toBytes()); // "\x01\x55"
buf.write(cast(ubyte) 2);
buf.align4(0x55);
writeln(buf.toBytes()); // "\x01\x55\x02\x55"
buf.write(cast(ubyte) 3);
buf.alignSize(8, 0x55);
writeln(buf.toBytes()); // "\x01\x55\x02\x55\x03\x55\x55\x55"
pure nothrow @safe void clear();
Clear the data in the buffer
pure nothrow @safe void align2(ubyte val = 0);
Optimize common special case alignSize(2)
Parameters:
ubyte val Value to fill, defaults to 0.
pure nothrow @safe void align4(ubyte val = 0);
Optimize common special case alignSize(4)
Parameters:
ubyte val Value to fill, defaults to 0.
const pure nothrow @safe string toString();
Convert internal buffer to array of chars.
nothrow @trusted void vprintf(scope string format, va_list args);
Append output of C's vprintf() to internal buffer.
@trusted void printf(scope string format, ...);
Append output of C's printf() to internal buffer.
void writef(Char, A...)(scope const(Char)[] fmt, A args);

void writef(alias fmt, A...)(A args)
if (isSomeString!(typeof(fmt)));
Formats and writes its arguments in text format to the OutBuffer.
Parameters:
const(Char)[] fmt format string as described in std.format.formattedWrite
A args arguments to be formatted
Examples:
OutBuffer b = new OutBuffer();
b.writef("a%sb", 16);
writeln(b.toString()); // "a16b"
Examples:
OutBuffer b = new OutBuffer();
b.writef!"a%sb"(16);
writeln(b.toString()); // "a16b"
void writefln(Char, A...)(scope const(Char)[] fmt, A args);

void writefln(alias fmt, A...)(A args)
if (isSomeString!(typeof(fmt)));
Formats and writes its arguments in text format to the OutBuffer, followed by a newline.
Parameters:
const(Char)[] fmt format string as described in std.format.formattedWrite
A args arguments to be formatted
Examples:
OutBuffer b = new OutBuffer();
b.writefln("a%sb", 16);
writeln(b.toString()); // "a16b\n"
Examples:
OutBuffer b = new OutBuffer();
b.writefln!"a%sb"(16);
writeln(b.toString()); // "a16b\n"
pure nothrow @safe void spread(size_t index, size_t nbytes);
At offset index into buffer, create nbytes of space by shifting upwards all data past index.