mirror of
https://git.code.sf.net/p/quake/quakeforge
synced 2024-12-24 11:41:02 +00:00
1448 lines
26 KiB
Text
1448 lines
26 KiB
Text
#LyX 1.1 created this file. For more info see http://www.lyx.org/
|
|
\lyxformat 218
|
|
\textclass scrbook
|
|
\language american
|
|
\inputencoding latin1
|
|
\fontscheme pslatex
|
|
\graphics default
|
|
\paperfontsize 12
|
|
\spacing single
|
|
\papersize letterpaper
|
|
\paperpackage a4
|
|
\use_geometry 1
|
|
\use_amsmath 0
|
|
\paperorientation portrait
|
|
\secnumdepth 2
|
|
\tocdepth 2
|
|
\paragraph_separation skip
|
|
\defskip medskip
|
|
\quotes_language english
|
|
\quotes_times 2
|
|
\papercolumns 1
|
|
\papersides 2
|
|
\paperpagestyle headings
|
|
|
|
\layout Title
|
|
|
|
The Ruamoko Programming Language
|
|
\layout Author
|
|
|
|
Bill Currie
|
|
\begin_inset Formula \( \bullet \)
|
|
\end_inset
|
|
|
|
Jeff Teunissen
|
|
\layout Publishers
|
|
|
|
QuakeForge Press
|
|
\newline
|
|
;-)
|
|
\layout Uppertitleback
|
|
|
|
This manual is free; you can redistribute it and/or modify it under the
|
|
terms of the GNU General Public License as published by the Free Software
|
|
Foundation; either version 2 of the License, or (at your option) any later
|
|
version.
|
|
\newline
|
|
|
|
\newline
|
|
This manual is distributed in the hope that it will be useful, but WITHOUT
|
|
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
|
FOR A PARTICULAR PURPOSE.
|
|
See the GNU General Public License for more details.
|
|
\newline
|
|
|
|
\newline
|
|
You should have received a copy of the GNU General Public License along
|
|
with this manual: if not, write to:
|
|
\newline
|
|
|
|
\newline
|
|
Free Software Foundation, Inc.
|
|
\newline
|
|
59 Temple Place - Suite 330
|
|
\newline
|
|
Boston MA 02111-1307
|
|
\newline
|
|
USA
|
|
\layout Lowertitleback
|
|
|
|
Copyright © 2002 Bill Currie and Jeff Teunissen
|
|
\layout Standard
|
|
|
|
|
|
\begin_inset LatexCommand \tableofcontents{}
|
|
|
|
\end_inset
|
|
|
|
|
|
\layout Addchap
|
|
|
|
Preface
|
|
\layout Standard
|
|
|
|
In December 1996, Id Software released
|
|
\emph on
|
|
Quake
|
|
\emph default
|
|
to the world.
|
|
It's doubtful that they knew at the time that it would spark a revolution
|
|
-- but such a revolution happened.
|
|
To the game industry's surprise, people were getting the game not just
|
|
to play it, but to
|
|
\emph on
|
|
change
|
|
\emph default
|
|
it\SpecialChar \@.
|
|
For the first time, people could make whole new games based on the Quake
|
|
engine without having to rewrite the whole game -- and in fact you couldn't
|
|
rewrite the whole game, because the main source code wasn't available to
|
|
the general public.
|
|
What
|
|
\series bold
|
|
was
|
|
\series default
|
|
available was something new -- the game wasn't just a game, it was a virtual
|
|
machine that had a byte-code instruction set -- and it had a compiler that
|
|
you could use to make new games to run inside that engine.
|
|
The language (called
|
|
\emph on
|
|
QuakeC
|
|
\emph default
|
|
) was kind of crude, and the compiler was even more crude -- but it was
|
|
a revolutionary development.
|
|
\layout Standard
|
|
|
|
Now, let's fast-forward to another December -- this time, December 1999.
|
|
In another revolutionary move, Id Software released the source code to
|
|
the complete Quake engine.
|
|
This gave many people the opportunity to do a lot more than just make
|
|
\begin_inset Quotes eld
|
|
\end_inset
|
|
|
|
mods
|
|
\begin_inset Quotes erd
|
|
\end_inset
|
|
|
|
for Quake.
|
|
Instead, people could make all-new games without using Quake itself.
|
|
Many projects started up around this source code, with many aims\SpecialChar \ldots{}
|
|
but one
|
|
project grew to be the most dominant: That project is
|
|
\emph on
|
|
QuakeForge
|
|
\emph default
|
|
.
|
|
\layout Standard
|
|
|
|
QuakeForge has developed a number of interesting things involving the Quake
|
|
engine, but most of them are beyond the scope of this manual.
|
|
This manual documents the
|
|
\emph on
|
|
Ruamoko
|
|
\begin_float footnote
|
|
\layout Standard
|
|
|
|
The name Ruamoko comes from the Maori name for their god of volcanoes and
|
|
earthquakes.
|
|
According to myth, Ruamoko is not yet born, and when he shakes inside the
|
|
Earth-mother, the world shakes.
|
|
\end_float
|
|
language, a language based on Id Software's QuakeC, but which has been
|
|
expanded in ways far beyond the original language.
|
|
\layout Chapter
|
|
|
|
A Tutorial Introduction
|
|
\layout Standard
|
|
|
|
Let us begin with a quick introduction to Ruamoko.
|
|
Our aim here is to show the basic elements of the language in real programs,
|
|
but without getting bogged down in details or rules.
|
|
At this point, we're not even trying to be complete, or even precise (except
|
|
that the examples are meant to be correct).
|
|
We want to get you as quickly as possible to the point where you can write
|
|
useful programs, and to do that we have to concentrate on the basics: variables
|
|
and constants, arithmetic, flow control, functions, and the rudiments of
|
|
input and output.
|
|
We are intentionally leaving out of this chapter features of Ruamoko that
|
|
are important for writing bigger programs, or programs to run in an actual
|
|
Quake engine.
|
|
These include entities, structures, pointers, most of the operators, objects,
|
|
and the standard builtin library.
|
|
\layout Standard
|
|
|
|
This approach has its drawbacks.
|
|
Most notable is that the complete story on any particular language feature
|
|
is not found here, and the brief tutorial, just by being brief, may be
|
|
misleading.
|
|
And because the examples don't use the full power of Ruamoko, they may
|
|
not be as elegant or concise as they could be; we
|
|
\series bold
|
|
have
|
|
\series default
|
|
tried to minimize these effects, but be warned.
|
|
Another drawback is that later chapters will repeat some of what's presented
|
|
here.
|
|
We hope that the repetition will help more than it annoys.
|
|
\layout Standard
|
|
|
|
In any case, experienced programmers should be able to get an idea, from
|
|
this chapter, of some of the things that can be done in Ruamoko, for their
|
|
own needs.
|
|
Beginners should supplement it by writing small, similar programs of their
|
|
own.
|
|
Both groups can use it as a framework on which to hang the more detailed
|
|
descriptions that begin in later chapters.
|
|
\layout Section
|
|
|
|
Getting Started
|
|
\layout Standard
|
|
|
|
The best way to learn a new programming language is by writing programs
|
|
in it.
|
|
The first program one writes is almost always the same for all new languages:
|
|
print the phrase
|
|
\begin_inset Quotes eld
|
|
\end_inset
|
|
|
|
Hello, world!
|
|
\begin_inset Quotes erd
|
|
\end_inset
|
|
|
|
on the screen.
|
|
\layout Standard
|
|
|
|
This is the big hurdle.
|
|
To get past it, you have to be able to create the program text somewhere,
|
|
compile it, load it successfully, load it, run it, and find out where the
|
|
output went.
|
|
With these mechanical details mastered, everything else is relatively easy.
|
|
\layout Standard
|
|
|
|
In Ruamoko, the program to print
|
|
\begin_inset Quotes eld
|
|
\end_inset
|
|
|
|
Hello, world!
|
|
\begin_inset Quotes erd
|
|
\end_inset
|
|
|
|
is:
|
|
\layout LyX-Code
|
|
|
|
#include <qwaq/globals.rh>
|
|
\newline
|
|
#include <qwaq/fields.rh>
|
|
\newline
|
|
#include <qwaq/builtins.rh>
|
|
\newline
|
|
|
|
\newline
|
|
void () main =
|
|
\newline
|
|
{
|
|
\newline
|
|
printf ("Hello, world!
|
|
\backslash
|
|
n");
|
|
\newline
|
|
};
|
|
\layout Standard
|
|
|
|
To run this program, you first have to compile it.
|
|
To compile it, you need to save the source code into a file (for example,
|
|
|
|
\family typewriter
|
|
hello.r
|
|
\family default
|
|
), and create a
|
|
\family typewriter
|
|
progs.src
|
|
\family default
|
|
file to tell the compiler how to compile it.
|
|
Here is an example
|
|
\family typewriter
|
|
progs.src
|
|
\family default
|
|
file:
|
|
\layout LyX-Code
|
|
|
|
qwaq.dat
|
|
\newline
|
|
hello.r
|
|
\layout Standard
|
|
|
|
The first line of
|
|
\family typewriter
|
|
progs.src
|
|
\family default
|
|
tells the compiler the name of the compiled object file that it is supposed
|
|
to save to disk after compilation.
|
|
Following lines tell it the names of files that are to be used to compile
|
|
that object file.
|
|
To compile the source, issue the command
|
|
\layout LyX-Code
|
|
|
|
qfcc
|
|
\layout Standard
|
|
|
|
If you haven't screwed anything up, such as omitting a character or misspelling
|
|
something, the compilation will proceed silently.
|
|
You should be rewarded with something that looks something like the following:
|
|
\layout LyX-Code
|
|
|
|
208 strofs
|
|
\newline
|
|
4 statements
|
|
\newline
|
|
14 functions
|
|
\newline
|
|
30 globaldefs
|
|
\newline
|
|
0 locals size ((null))
|
|
\newline
|
|
8 fielddefs
|
|
\newline
|
|
52 pr_globals
|
|
\newline
|
|
6 entityfields
|
|
\newline
|
|
1316 TOTAL SIZE
|
|
\newline
|
|
Compilation time: 0.0365 seconds.
|
|
\layout Standard
|
|
|
|
You run
|
|
\family typewriter
|
|
qwaq.dat
|
|
\family default
|
|
by issuing the command
|
|
\layout LyX-Code
|
|
|
|
qwaq
|
|
\layout Standard
|
|
|
|
the program should print
|
|
\layout LyX-Code
|
|
|
|
Hello, world!
|
|
\layout Standard
|
|
|
|
to your screen.
|
|
\layout Standard
|
|
|
|
Now, for some explanations regarding the program itself.
|
|
All Ruamoko programs, regardless of size, consist mainly of
|
|
\emph on
|
|
functions
|
|
\emph default
|
|
and
|
|
\emph on
|
|
variables
|
|
\emph default
|
|
.
|
|
A function contains statements that tell the compiler what computing operations
|
|
you want to do, and variables store values used during the operation of
|
|
the program.
|
|
Ruamoko functions are roughly equivalent to C's functions, or Pascal's
|
|
procedures and functions.
|
|
Our example is a function called
|
|
\family typewriter
|
|
main
|
|
\family default
|
|
.
|
|
You can create functions with just about any name you like, but
|
|
\begin_inset Quotes eld
|
|
\end_inset
|
|
|
|
|
|
\family typewriter
|
|
main
|
|
\family default
|
|
|
|
\begin_inset Quotes erd
|
|
\end_inset
|
|
|
|
is special -- program execution begins there
|
|
\begin_float footnote
|
|
\layout Standard
|
|
|
|
This is not precisely true.
|
|
When used in a game engine, there are certain other functions that are
|
|
called by the engine during the course of a game.
|
|
\end_float
|
|
.
|
|
This means that every program must have a
|
|
\family typewriter
|
|
main
|
|
\family default
|
|
function somewhere.
|
|
\layout Standard
|
|
|
|
Main will usually call other functions to do its job -- some of them you
|
|
write, and some of them are provided by the virtual machine your program
|
|
runs inside.
|
|
The first lines of the program,
|
|
\layout LyX-Code
|
|
|
|
#include <qwaq/globals.rh>
|
|
\newline
|
|
#include <qwaq/fields.rh>
|
|
\newline
|
|
#include <qwaq/builtins.rh>
|
|
\layout Standard
|
|
|
|
tell the compiler to include information about the standard variables, constants
|
|
,
|
|
\emph on
|
|
fields
|
|
\emph default
|
|
, and
|
|
\emph on
|
|
builtins
|
|
\emph default
|
|
(also known as
|
|
\emph on
|
|
engine functions
|
|
\emph default
|
|
) provided by the environment
|
|
\begin_float footnote
|
|
\layout Standard
|
|
|
|
The environment will be described later.
|
|
\end_float
|
|
.
|
|
\layout Standard
|
|
|
|
One way of communicating data between functions is for the calling function
|
|
to provide a list of values, called arguments, to the function it calls.
|
|
The parentheses after the function's name surround the argument list.
|
|
In this example, main is defined to be a function that expects no arguments,
|
|
which is indicated by an empty list:\SpecialChar ~
|
|
|
|
\family typewriter
|
|
()
|
|
\family default
|
|
.
|
|
\layout Standard
|
|
|
|
The statements of a function are enclosed in curly braces,\SpecialChar ~
|
|
|
|
\family typewriter
|
|
{}
|
|
\family default
|
|
.
|
|
The function
|
|
\family typewriter
|
|
main
|
|
\family default
|
|
contains only one statement,
|
|
\layout LyX-Code
|
|
|
|
printf ("Hello, world!
|
|
\backslash
|
|
n");
|
|
\layout Standard
|
|
|
|
A function is called by giving its name, followed by a list of arguments
|
|
enclosed by parentheses, so this calls the function
|
|
\family typewriter
|
|
printf
|
|
\family default
|
|
with the argument
|
|
\family typewriter
|
|
"Hello, world!
|
|
\backslash
|
|
n"
|
|
\family default
|
|
.
|
|
|
|
\family typewriter
|
|
printf
|
|
\family default
|
|
is a builtin function that prints output, in this case the string of characters
|
|
between the quotes.
|
|
\layout Standard
|
|
|
|
A sequence of characters between double quotes, like
|
|
\family typewriter
|
|
"Hello, world!
|
|
\backslash
|
|
n"
|
|
\family default
|
|
, is called a
|
|
\emph on
|
|
string constant
|
|
\emph default
|
|
or simply a
|
|
\emph on
|
|
string
|
|
\emph default
|
|
.
|
|
For the moment, our only use of strings will be as arguments for
|
|
\family typewriter
|
|
printf
|
|
\family default
|
|
and other functions.
|
|
\layout Standard
|
|
|
|
The sequence
|
|
\family typewriter
|
|
|
|
\backslash
|
|
n
|
|
\family default
|
|
in the string is Ruamoko notation for the
|
|
\emph on
|
|
newline character
|
|
\emph default
|
|
, which when printed tells the terminal (or a game client) to advance to
|
|
the next line in the output.
|
|
If you leave out the
|
|
\family typewriter
|
|
|
|
\backslash
|
|
n
|
|
\family default
|
|
, you will find that there is no advance after the character string is printed.
|
|
You must use
|
|
\family typewriter
|
|
|
|
\backslash
|
|
n
|
|
\family default
|
|
to include a newline character in the printf argument; if you try something
|
|
like
|
|
\layout LyX-Code
|
|
|
|
printf ("Hello, world!
|
|
\newline
|
|
");
|
|
\layout Standard
|
|
|
|
the Ruamoko compiler will give you an error message.
|
|
\layout Standard
|
|
|
|
|
|
\family typewriter
|
|
printf
|
|
\family default
|
|
never supplies a newline automatically, so several calls may be used to
|
|
build up an output line in stages.
|
|
Our first program could just as easily been written as
|
|
\layout LyX-Code
|
|
|
|
#include <qwaq/globals.rh>
|
|
\newline
|
|
#include <qwaq/fields.rh>
|
|
\newline
|
|
#include <qwaq/builtins.rh>
|
|
\newline
|
|
|
|
\newline
|
|
void () main =
|
|
\newline
|
|
{
|
|
\newline
|
|
printf ("Hello, ");
|
|
\newline
|
|
printf ("world!");
|
|
\newline
|
|
printf ("
|
|
\backslash
|
|
n");
|
|
\newline
|
|
};
|
|
\layout Standard
|
|
|
|
and it would have produced identical output.
|
|
\layout Standard
|
|
|
|
Note that
|
|
\backslash
|
|
n represents only a single character.
|
|
An escape character like
|
|
\backslash
|
|
n gives you a general way to express hard-to-type or invisible characters.
|
|
Among the others are
|
|
\backslash
|
|
t for a tab,
|
|
\backslash
|
|
b for a backspace,
|
|
\backslash
|
|
" for a double-quote, and
|
|
\backslash
|
|
|
|
\backslash
|
|
for the backslash character itself.
|
|
There is a complete list in [section]
|
|
\layout Section
|
|
|
|
Variables and Mathematical Expressions
|
|
\layout Chapter
|
|
|
|
Language Reference
|
|
\layout Standard
|
|
|
|
This is currently just new stuff in
|
|
\family typewriter
|
|
\series bold
|
|
qfcc
|
|
\family default
|
|
\series default
|
|
.
|
|
\layout Section
|
|
|
|
New Type Features
|
|
\layout Subsection
|
|
|
|
New Types
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
integer
|
|
\family default
|
|
32 bit signed integer
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
id
|
|
\family default
|
|
generic object pointer
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
Class
|
|
\family default
|
|
class object pointer
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
Protocol
|
|
\family default
|
|
protocol object pointer
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
Method
|
|
\family default
|
|
method pointer
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
SEL
|
|
\family default
|
|
selector
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
IMP
|
|
\family default
|
|
message implementation
|
|
\layout Standard
|
|
|
|
|
|
\family typewriter
|
|
id
|
|
\family default
|
|
,
|
|
\family typewriter
|
|
Class
|
|
\family default
|
|
,
|
|
\family typewriter
|
|
Protocol
|
|
\family default
|
|
,
|
|
\family typewriter
|
|
Method
|
|
\family default
|
|
,
|
|
\family typewriter
|
|
SEL
|
|
\family default
|
|
and
|
|
\family typewriter
|
|
IMP
|
|
\family default
|
|
are part of
|
|
\family typewriter
|
|
\series bold
|
|
qfcc
|
|
\family default
|
|
\series default
|
|
's Objective-QC extensions.
|
|
\layout Subsection
|
|
|
|
Enumerators
|
|
\layout Standard
|
|
|
|
as per C
|
|
\layout Subsection
|
|
|
|
Structures
|
|
\layout LyX-Code
|
|
|
|
struct foo {
|
|
\newline
|
|
integer bar;
|
|
\newline
|
|
float baz;
|
|
\newline
|
|
void () func;
|
|
\newline
|
|
};
|
|
\layout Standard
|
|
|
|
Structures with no elements can be declared for making opaque types (particularl
|
|
y useful for engine interface functions).
|
|
\layout Subsection
|
|
|
|
Arrays
|
|
\layout LyX-Code
|
|
|
|
integer [13] array;
|
|
\layout Subsection
|
|
|
|
Pointers
|
|
\layout Standard
|
|
|
|
Pointers are declared the same way as arrays, but with no number in the
|
|
|
|
\family typewriter
|
|
[]
|
|
\family default
|
|
s.
|
|
In fact, arrays are just pointers with limited (compile-time) bounds checking
|
|
(constant indices).
|
|
\layout Subsection
|
|
|
|
Complex types
|
|
\layout Standard
|
|
|
|
Complex types can be created by nesting type declarations within
|
|
\family typewriter
|
|
()
|
|
\family default
|
|
s.
|
|
e.g.:
|
|
\layout LyX-Code
|
|
|
|
(.float) (string name) find_field;
|
|
\layout Standard
|
|
|
|
declares a function (
|
|
\family typewriter
|
|
find_field
|
|
\family default
|
|
) taking a string parameter and returning a float field `offset'.
|
|
Without the
|
|
\family typewriter
|
|
()
|
|
\family default
|
|
s around the
|
|
\family typewriter
|
|
.float
|
|
\family default
|
|
, the declaration would be a function field.
|
|
\layout Subsection
|
|
|
|
|
|
\family typewriter
|
|
typedef
|
|
\layout Standard
|
|
|
|
By using
|
|
\family typewriter
|
|
typedef
|
|
\family default
|
|
complex types can be given symbolic names.
|
|
e.g.:
|
|
\layout LyX-Code
|
|
|
|
struct foo_s {};
|
|
\newline
|
|
typedef foo_s [] foo_t;
|
|
\layout Standard
|
|
|
|
creates type
|
|
\family typewriter
|
|
foo_t
|
|
\family default
|
|
which is a pointer to the structure
|
|
\family typewriter
|
|
foo_s
|
|
\family default
|
|
(which happens to be opaque).
|
|
\layout Subsection
|
|
|
|
Variable-argument functions
|
|
\layout Standard
|
|
|
|
Typed parameters preceding the ellipsis are allowed, e.g.:
|
|
\family typewriter
|
|
void (string fmt, ...) printf;
|
|
\layout Standard
|
|
|
|
More importantly, it is now possible to write vararg functions in QC.
|
|
|
|
\family typewriter
|
|
@argc
|
|
\family default
|
|
gives the number of parameters passed through the ellipsis and
|
|
\family typewriter
|
|
@argv
|
|
\family default
|
|
is an array of vectors representing the parameters passed through
|
|
\family typewriter
|
|
...
|
|
\family default
|
|
.
|
|
\layout Standard
|
|
|
|
|
|
\series bold
|
|
\emph on
|
|
Warning: attempting to pass
|
|
\family typewriter
|
|
@argv
|
|
\family default
|
|
to a non-engine function will not work.
|
|
This is because of changes in how local variables are handled by the compiler.
|
|
\layout Subsection
|
|
|
|
Improved type checking
|
|
\layout Standard
|
|
|
|
Function parameters and return types are are fully checked, including the
|
|
number of parameters passed to a function.
|
|
Functions with different return types and/or different parameter types
|
|
or counts are distinct types and mixing them up will cause a type mismatch
|
|
error.
|
|
Similar for pointers to various types.
|
|
\layout Section
|
|
|
|
Variables
|
|
\layout Subsection
|
|
|
|
Local variables
|
|
\layout Subsubsection
|
|
|
|
Initialization
|
|
\layout Standard
|
|
|
|
Local variables of basic types can now be initialized when declared.
|
|
e,g,
|
|
\layout Verse
|
|
|
|
|
|
\family typewriter
|
|
local integer elite = 31337;
|
|
\layout Subsubsection
|
|
|
|
Unused variables
|
|
\layout Standard
|
|
|
|
Local variables that are declared but not used produce a warning.
|
|
\layout Subsubsection
|
|
|
|
Uninitialized variables
|
|
\layout Standard
|
|
|
|
Checks are done to ensure that local variables have been initialized before
|
|
being used.
|
|
However, these checks are not perfect and false positives are very likely
|
|
in complex code.
|
|
Occurrences of false negatives are not known, but the possibility of their
|
|
existence remains and any examples of false negatives should be reported
|
|
as bugs.
|
|
\layout Subsection
|
|
|
|
Complex global variables
|
|
\layout Standard
|
|
|
|
Global array variables can be initialized using
|
|
\family typewriter
|
|
= {
|
|
\emph on
|
|
element-list
|
|
\emph default
|
|
};
|
|
\family default
|
|
.
|
|
Element lists may be nested using
|
|
\family typewriter
|
|
{}
|
|
\family default
|
|
.
|
|
Structures cannot currently be initialized, but this is a FIXME :)
|
|
\layout Subsection
|
|
|
|
Magic variables
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
@self
|
|
\family default
|
|
Automagically declared entity variable the engine will use for
|
|
\family typewriter
|
|
touch
|
|
\family default
|
|
and
|
|
\family typewriter
|
|
think
|
|
\family default
|
|
functions.
|
|
This allows
|
|
\family typewriter
|
|
self
|
|
\family default
|
|
to be used as the object hidden parameter in methods.
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
@this
|
|
\family default
|
|
Automagically declared
|
|
\family typewriter
|
|
id
|
|
\family default
|
|
field that the engine expects to point to the object associated with the
|
|
entity.
|
|
The engine will use this field, if it exists, to set the
|
|
\family typewriter
|
|
self
|
|
\family default
|
|
parameter to
|
|
\family typewriter
|
|
touch
|
|
\family default
|
|
and
|
|
\family typewriter
|
|
think
|
|
\family default
|
|
methods (the engine assumes it's calling a method rather than a function
|
|
if the @this field is used.
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
@argc
|
|
\family default
|
|
Number of parameters passed through
|
|
\family typewriter
|
|
...
|
|
|
|
\family default
|
|
in vararg functions.
|
|
Not valid elsewhere.
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
@argv
|
|
\family default
|
|
Array of vectors representing the parameters passed through
|
|
\family typewriter
|
|
...
|
|
|
|
\family default
|
|
in vararg functions.
|
|
Not valid elsewhere.
|
|
\layout Section
|
|
|
|
Code constructs
|
|
\layout Subsection
|
|
|
|
|
|
\family typewriter
|
|
break
|
|
\layout Standard
|
|
|
|
The
|
|
\family typewriter
|
|
break
|
|
\family default
|
|
statement can be used to leave a loop (
|
|
\family typewriter
|
|
while
|
|
\family default
|
|
,
|
|
\family typewriter
|
|
do
|
|
\family default
|
|
...
|
|
|
|
\family typewriter
|
|
while
|
|
\family default
|
|
, or
|
|
\family typewriter
|
|
for
|
|
\family default
|
|
) prematurely.
|
|
The
|
|
\family typewriter
|
|
break
|
|
\family default
|
|
statement is also used to leave a
|
|
\family typewriter
|
|
switch
|
|
\family default
|
|
statement.
|
|
\layout Subsection
|
|
|
|
|
|
\family typewriter
|
|
continue
|
|
\layout Standard
|
|
|
|
The
|
|
\family typewriter
|
|
continue
|
|
\family default
|
|
statement is used to jump to the beginning of a loop.
|
|
In
|
|
\family typewriter
|
|
for
|
|
\family default
|
|
loops, the test and post expressions are evaluated before continuing with
|
|
the loop.
|
|
\layout Subsection
|
|
|
|
|
|
\family typewriter
|
|
for
|
|
\layout Standard
|
|
|
|
The
|
|
\family typewriter
|
|
for
|
|
\family default
|
|
loop is:
|
|
\layout LyX-Code
|
|
|
|
for (
|
|
\emph on
|
|
initialization-expression
|
|
\emph default
|
|
;
|
|
\emph on
|
|
test-expression
|
|
\emph default
|
|
;
|
|
\emph on
|
|
post-expression
|
|
\emph default
|
|
)
|
|
\layout LyX-Code
|
|
|
|
|
|
\emph on
|
|
statement
|
|
\layout Standard
|
|
|
|
and is equivalent to
|
|
\layout LyX-Code
|
|
|
|
|
|
\emph on
|
|
initialization expression
|
|
\layout LyX-Code
|
|
|
|
while (
|
|
\emph on
|
|
test expression
|
|
\emph default
|
|
) {
|
|
\layout LyX-Code
|
|
|
|
|
|
\emph on
|
|
statement
|
|
\layout LyX-Code
|
|
|
|
|
|
\emph on
|
|
post expression
|
|
\layout LyX-Code
|
|
|
|
}
|
|
\layout Subsection
|
|
|
|
|
|
\family typewriter
|
|
switch
|
|
\layout Standard
|
|
|
|
The
|
|
\family typewriter
|
|
switch
|
|
\family default
|
|
statement is used to select between multiple code blocks based on the value
|
|
of an expression.
|
|
\layout LyX-Code
|
|
|
|
switch (
|
|
\emph on
|
|
test expression
|
|
\emph default
|
|
) {
|
|
\newline
|
|
case
|
|
\emph on
|
|
value
|
|
\emph default
|
|
:
|
|
\newline
|
|
|
|
\emph on
|
|
optional statements
|
|
\newline
|
|
|
|
\emph default
|
|
case
|
|
\emph on
|
|
value
|
|
\emph default
|
|
:
|
|
\newline
|
|
|
|
\emph on
|
|
optional statements
|
|
\emph default
|
|
|
|
\newline
|
|
default:
|
|
\newline
|
|
|
|
\emph on
|
|
optional statements
|
|
\emph default
|
|
|
|
\newline
|
|
}
|
|
\layout Standard
|
|
|
|
Code execution starts at the selected
|
|
\family typewriter
|
|
case
|
|
\family default
|
|
and continues on to the end of the switch block.
|
|
Following
|
|
\family typewriter
|
|
case
|
|
\family default
|
|
s do
|
|
\emph on
|
|
not
|
|
\emph default
|
|
affect code execution.
|
|
If this behavior is not desired, as is usual, then a
|
|
\family typewriter
|
|
break
|
|
\family default
|
|
statement is required to cause the code to jump to the end of the
|
|
\family typewriter
|
|
switch
|
|
\family default
|
|
, skipping any intervening code.
|
|
That is, just like C.
|
|
\layout Subsubsection
|
|
|
|
|
|
\family typewriter
|
|
\emph on
|
|
test expression
|
|
\layout Standard
|
|
|
|
The test expression may result in a float, string or integer value.
|
|
\layout Subsubsection
|
|
|
|
|
|
\family typewriter
|
|
case
|
|
\emph on
|
|
value
|
|
\layout Verse
|
|
|
|
|
|
\family typewriter
|
|
case
|
|
\emph on
|
|
value
|
|
\emph default
|
|
:
|
|
\layout Standard
|
|
|
|
The case value may be of any constant type consistent with the test expression
|
|
of the
|
|
\family typewriter
|
|
switch
|
|
\family default
|
|
.
|
|
\layout Subsubsection
|
|
|
|
|
|
\family typewriter
|
|
default
|
|
\layout Standard
|
|
|
|
If specified, this is where execution will go when no
|
|
\family typewriter
|
|
case
|
|
\family default
|
|
has been selected by the test expression.
|
|
If not specified, and no
|
|
\family typewriter
|
|
case
|
|
\family default
|
|
has been selected by the test expression, the
|
|
\family typewriter
|
|
switch
|
|
\family default
|
|
does not execute any code within the block.
|
|
\layout Section
|
|
|
|
Expressions
|
|
\layout Subsection
|
|
|
|
Binary
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
<<\SpecialChar ~
|
|
>>
|
|
\family default
|
|
bit shift left and right
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
^
|
|
\family default
|
|
bitwise exclusive or
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
%
|
|
\family default
|
|
modulus
|
|
\layout Subsubsection
|
|
|
|
Assignment
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
\emph on
|
|
op
|
|
\emph default
|
|
=
|
|
\family default
|
|
equivalent to
|
|
\family typewriter
|
|
a = a
|
|
\emph on
|
|
op
|
|
\emph default
|
|
b
|
|
\family default
|
|
.
|
|
\layout Subsection
|
|
|
|
Unary
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
~
|
|
\family default
|
|
bitwise not
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
&
|
|
\family default
|
|
address
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
++
|
|
\emph on
|
|
e
|
|
\emph default
|
|
\SpecialChar ~
|
|
--
|
|
\emph on
|
|
e
|
|
\family default
|
|
\emph default
|
|
pre-increment and decrement
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
\emph on
|
|
e
|
|
\emph default
|
|
++\SpecialChar ~
|
|
|
|
\emph on
|
|
e
|
|
\emph default
|
|
--
|
|
\family default
|
|
post-increment and decrement
|
|
\layout Subsection
|
|
|
|
Other
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
\emph on
|
|
type\SpecialChar ~
|
|
|
|
\emph default
|
|
(
|
|
\emph on
|
|
expr
|
|
\emph default
|
|
)
|
|
\family default
|
|
cast expression.
|
|
Only works for converting between integer and float types and between pointer
|
|
types.
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
\emph on
|
|
expr
|
|
\emph default
|
|
[
|
|
\emph on
|
|
expr
|
|
\emph default
|
|
]
|
|
\family default
|
|
array indexing.
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
\emph on
|
|
expr
|
|
\emph default
|
|
?
|
|
\emph on
|
|
expr
|
|
\emph default
|
|
:
|
|
\emph on
|
|
expr
|
|
\family default
|
|
\emph default
|
|
C's trinary expression
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
[
|
|
\emph on
|
|
expr
|
|
\emph default
|
|
\SpecialChar ~
|
|
|
|
\emph on
|
|
exprs
|
|
\emph default
|
|
]
|
|
\family default
|
|
Objective-QC message
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
@selector(
|
|
\emph on
|
|
exprs
|
|
\emph default
|
|
)
|
|
\family default
|
|
Objective-QC selector expression
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
@protocol(
|
|
\emph on
|
|
name
|
|
\emph default
|
|
)
|
|
\family default
|
|
Objective-QC protocol expression
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
@encode(
|
|
\emph on
|
|
type
|
|
\emph default
|
|
)
|
|
\family default
|
|
Objective-QC type encoding expression
|
|
\layout List
|
|
\labelwidthstring 00.00.0000
|
|
|
|
|
|
\family typewriter
|
|
@
|
|
\emph on
|
|
string
|
|
\family default
|
|
\emph default
|
|
Objective-QC string object.
|
|
Currently identical to a normal QC string.
|
|
\the_end
|