Builtin Functions

Spice offers five builtin functions out of the box. Those can be used anywhere without having to be imported manually and can be used to establish a minimal setup for testing or the like.

The printf builtin¶

Printf works the same as the printf function in C and is designed for printing a string to the standard text output (cout).

Signature¶

int printf(string template, ...args)

template: Template string, which can contain placeholders for values, passed as args to the printf builtin.
args: Arbitrary number of arguments of any type. The particular type and the order of the types have to match the placeholders of the template string.

Within the template string you can use control characters like the \n control character to achieve line breaks. This works on Linux and Windows the same way.

Placeholders¶

Usage example¶

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printf("Here is a string: %s.\nAnd here is a double: %f", "Demo", 1.123);

The sizeof builtin¶

Sizeof returns the internal size of a variable, constant or type in bits. To get the size in bytes, simply divide the result by 8.

Signature¶

int sizeof(<any variable>) or int sizeof(type <any type>)

any variable: Variable or constant of any type, any type: Any data type

Usage example¶

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sizeof(12); // 32
sizeof(type int) // 32

int[9] intArray = [];
sizeof(intArray); // 9 * 32 = 288

sizeof("Hello World!"); // 64 (Strings are Char pointers internally)

The alignof builtin¶

Alignof returns the alignment of a variable, constant or type in bytes. To get the alignment in bits, simply multiply the result by 8.

Signature¶

int alignof(<any variable>) or int alignof(type <any type>)

any variable: Variable or constant of any type, any type: Any data type

Usage example¶

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alignof(12); // 4
sizeof(type int) // 4

DemoStruct s = DemoStruct{123, 56l, 12s, "String"};
sizeof(intArray); // 8 (the long value is the widest type in the struct)

sizeof("Hello World!"); // 8 (Strings are Char pointers internally)

The len builtin¶

Len returns the length of a Spice array in items.

Signature¶

int len(any[] variable)

variable: Variable of any array type.

Usage example¶

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len([1, 2, 3, 4]); // 4

string[5] stringArray = ["string1", "string2", "string3"];
len(stringArray); // 5

The panic builtin¶

Panic is used to terminate the program with an error message.

Signature¶

void panic(const Error& error)

error: Error object containing the error code and message.

Usage example¶

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panic(Error("This is an error message")));

The syscall builtin¶

Syscall is used to send a specific syscall to the underlying operating system. Up to six arguments in addition to the syscall number are allowed.

Signature¶

long syscall(unsigned short syscallNumber, ...args)

syscallNumber: Number of the syscall. See here for all Linux syscalls.

Usage example¶

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// Use write syscall to print "Hello World!"
const string str = "Hello World!";
syscall(/* syscall no = write */ 1s, /*fd = stdout*/ 1, /* buffer */ str, len(str));