RCXString

Reference Counted Array. Configured with character type E, maximum length for the small string optimization, and the allocation function, which must have the same semantics as realloc.

struct RCXString (

E = immutable char

size_t maxSmallSize = 23

alias realloc = GC.realloc

) {

pure nothrow

enum maxSmallLength;

size_t length();

alias opDollar = length;

string toArray();

this(C[] s);

size_t capacity();

void opOpAssign(const(ME)[] s);

void opOpAssign(RCXString s);

bool empty();

auto front();

dchar back();

E opIndex(size_t n);

void popFront();

void popBack();

auto opSlice();

auto opSlice(size_t b, size_t e);

RCXString opBinary(RCXString s);

RCXString opBinary(const(ME)[] s);

RCXString opBinaryRight(const(E)[] s);

}

Constructors

this this(C[] s): Construct a RCXString from a slice s.

Destructor

A destructor is present on this object, but not explicitly documented in the source.

Postblit

A postblit is present on this object, but not explicitly documented in the source.

Members

Aliases

opDollar alias opDollar = length: Returns the length of the string

Functions

back dchar back(): Returns the last code point of this.
capacity size_t capacity(): Returns the maximum number of character this string can store without requesting more memory.
empty bool empty(): Returns true iff this is empty
front auto front(): Returns the first code point of this.
length size_t length(): Returns the length of the string
opBinary RCXString opBinary(RCXString s)
RCXString opBinary(const(ME)[] s): Returns the concatenation of this with s.
opBinaryRight RCXString opBinaryRight(const(E)[] s): Returns the concatenation of s with this.
opIndex E opIndex(size_t n): Returns the nth code unit in this.
opOpAssign void opOpAssign(const(ME)[] s)
void opOpAssign(RCXString s): Appends s to this.
opSlice auto opSlice()
auto opSlice(size_t b, size_t e): Returns a slice to the entire string or a portion of it.
popBack void popBack(): Discards the last code point
popFront void popFront(): Discards the first code point
toArray string toArray(): Needed for correct printing in other modules

Examples

verify UTF-8 storage

string s = "åäö";
RCString rcs = s;
assert(rcs.length == 6);
import std.algorithm : count;
assert(rcs.count == 3);
assert(rcs.front == 'å');
rcs.popFront();
assert(rcs.front == 'ä');
rcs.popFront();
assert(rcs.front == 'ö');
rcs.popFront();
assert(rcs.empty);

shows performance increase for SSO over built-in string

1 enum maxSmallSize = 23;
2 alias S = RCXString!(immutable char, maxSmallSize);
3 
4 import std.datetime: StopWatch, Duration;
5 import std.conv : to;
6 import std.stdio;
7 
8 enum n = 2^^21;
9 
10 StopWatch sw;
11 
12 sw.reset;
13 sw.start;
14 char[maxSmallSize] ss;
15 foreach (i; 0 .. n)
16 {
17     auto x = S(ss);
18 }
19 sw.stop;
20 auto timeRCString = sw.peek().msecs;
21 writeln("> RCString took ", sw.peek().to!Duration);
22 
23 sw.reset;
24 sw.start;
25 foreach (i; 0 .. n)
26 {
27     string x = ss.idup;
28 }
29 sw.stop;
30 auto timeString = sw.peek().msecs;
31 writeln("> Builtin string took ", sw.peek().to!Duration);
32 
33 writeln("> Speedup: ", timeString/timeRCString);