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1. Function parameters:
sum :: func(a: int, b: int) int { return a + b; }
foo :: func() { x := sum(1, 2); }
2. Multideclarations:
a, b := 1, 2; /* Multiple assignment */
r, g, b, a: u8; /* Type cascading */
x, y, z: i8 = …; /* Multiple undefined assignment */
3. Strings and arrays:
hello_utf8 := "Hello, World";
hello_utf8: []u8 = "Hello, World";
hello_utf16: []u16 = "Hello, World";
hello_utf32: []u32 = "Hello, World";
X :: 3;
xs := […]int{1, 2, 3}; /* Implicit length */
ys := [X]int{1, 2, 3}; /* Explicit length */
/* Assign specific indicies */
zs := […]int{
[2] = 123,
[4] = 321,
};
4. Conditionals:
if x > y {
…
} else if y < x {
…
} else {
…
}
5. Switch statements
if x == {
case 0;
…
case 1;
…
fallthrough; /* Explicit fallthrough; implicit break */
case 2;
…
default;
…
}
6. Loops
loop { … } /* Infinite loop */
loop x > y { … } /* While loop */
loop x: xs { … } /* Range/for loop */
loop i: N…M { … } /* Loop i from N to M (integers) */
/* Break- and continue a loop iteration */
loop x > y {
if x == 42 {
break;
}
if x & 1 == 1 {
continue;
}
…
}
/* Labeled break/continue */
outer :: loop {
loop x > y {
if x == 42 {
break outer;
}
}
}
7. Multiple return values from functions
swap :: func(x, y: int) int, int { return y, x; }
x, y := 1, 2;
x, y = swap(x, y);
/* Note that this is a function that returns a function! The
returned function is one that takes an int and returns nothing */
foo :: func() (int) { … }
8. Default parameters
foo :: func(x, y: int, flags: Flags = 0) { … }
9. Variadic parameters
foo :: func(xs: …int) {
for x: xs { … }
foo(xs…);
}
10. Structure types
City :: struct {
name, country: []u8;
population: int;
european := false;
}
växjö := City{"Växjö", "Sweden", 40'000, true};
são_paulo := City{
name = "São Paulo",
country = "Brazil",
population = 12.33e6,
};
11. Enumerations
/* enum T ≣ enum(0, x + 1) T*/
Animal :: enum u8 {
BEAR; /* 0 */
CAT; /* 1 */
DOG = 42;
SNAKE; /* 43 */
}
FileFlag :: enum(0, 1 << x) u8 {
READ; /* 0x01 */
WRITE; /* 0x02 */
TRUNC; /* 0x04 */
EXEC = 0b0100'0000; /* 0x40 */
CLOEXEC; /* 0x80 */
RDWR = .READ | .WRITE; /* 0x3 */
}
ByteSize :: enum(1, x * 1000) int {
B; /* 1 */
KB; /* 1'000 */
MB; /* 1'000'000 */
GB; /* 1'000'000'000 */
TB; /* 1'000'000'000'000 */
}
12. Enum-indexed arrays
Direction :: enum int { L; R; U; D; }
Vector2 :: struct { x, y: int; }
OFFSETS :: [Direction]Vector2{
.L = {-1, 0},
.R = {+1, 0},
.U = {0, +1},
.D = {0, -1},
}
$add :: func (x, y: Vector2) Vector2 {
return {x.x + y.x, x.y + y.y};
}
x := Vector2{2, 4};
x += OFFSETS[.U]; /* x == Vector2{2, 5} */
x += OFFSETS[3]; /* Illegal */
x += OFFSETS[Direction{3}]; /* Legal */
13. Operator overloading
$add :: func(x, y: T1) T2 { … }
$add, $sub, $mul, $div, etc.
$dot, $cross, $star, etc. for Unicode operators (⋅, ×, ⋆, etc.)
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