Built-in Functions

I/O

Chant

Prints a value to stdout with a newline.

Chant("Hello, world!");
Chant(42);
Chant([1, 2, 3]);

Whisper

Prints a value to stdout without a trailing newline.

Whisper("Enter name: ");

Inscribe

Reads a line of input from stdin.

Whisper("What is your name? ");
Runestone name is Inscribe();
Chant("Hello, " + name + "!");

File I/O

ReadScroll

Reads the entire contents of a file as a string.

Runestone contents is ReadScroll("data.txt");
Chant(contents);

WriteScroll

Writes a string to a file, overwriting any existing content.

WriteScroll("output.txt", "Hello from RuneLang!");

AppendScroll

Appends a string to a file without overwriting.

AppendScroll("log.txt", "New entry\n");

ScrollExists

Returns Truth if a file exists, Falsehood otherwise.

Quest begins when (ScrollExists("config.rune"))
    Chant("Config found.");
elsewise
    Chant("No config file.");
end of Quest

Math

Abs

Returns the absolute value.

Chant(Abs(-42));    // 42
Chant(Abs(42));     // 42
Chant(Abs(-3.14));  // 3.14

Pow

Raises a number to a power. Equivalent to the ** operator.

Chant(Pow(2, 10));  // 1024

Sqrt

Returns the square root as a Potion (float).

Chant(Sqrt(144));  // 12
Chant(Sqrt(2));    // 1.4142135623730951

Min / Max

Returns the smaller or larger of two numbers.

Chant(Min(5, 3));   // 3
Chant(Max(5, 3));   // 5

Floor / Ceil / Round

Chant(Floor(3.7));   // 3
Chant(Ceil(3.2));    // 4
Chant(Round(3.5));   // 4
Chant(Round(3.4));   // 3

Trigonometry

Chant(Sin(PI / 2));   // 1.0
Chant(Cos(0));        // 1.0
Chant(Tan(PI / 4));   // ~1.0

Log

Natural logarithm (base e).

Chant(Log(EULER));  // 1.0

Constants

Constant	Value	Description
PI	3.141592653589793	Pi
TAU	6.283185307179586	Tau (2 * Pi)
EULER	2.718281828459045	Euler’s number (e)
INFINITY	inf	Positive infinity

Utility

Measure

Returns the length of a string, array, or map.

Chant(Measure("hello"));    // 5
Chant(Measure([1, 2, 3]));  // 3

TypeOf

Returns the type name as a string.

Chant(TypeOf(42));        // "Countstone"
Chant(TypeOf("hello"));   // "Runestone"
Chant(TypeOf(3.14));      // "Potion"
Chant(TypeOf(Truth));     // "Flagstone"
Chant(TypeOf([1, 2]));    // "Scroll"
Chant(TypeOf({}));        // "Tome"

Transmute

Converts a value to a different type.

Transmute(42, "Runestone")     // "42"
Transmute("123", "Countstone") // 123
Transmute(3.14, "Countstone")  // 3
Transmute(42, "Potion")        // 42.0
Transmute(1, "Flagstone")      // Truth

Format

String formatting with {} placeholders.

Runestone msg is Format("{} has {} HP", "Thorin", 100);
Chant(msg);  // "Thorin has 100 HP"

Range

Creates an array of integers in a range.

Scroll r is Range(1, 6);     // [1, 2, 3, 4, 5]
Scroll r2 is Range(0, 10);   // [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

Roll

Generates a random integer between min and max (inclusive). Useful for D&D-style dice rolls.

Countstone d20 is Roll(1, 20);
Chant("You rolled a " + d20 + "!");

Assert

Throws an error if the condition is Falsehood.

Assert(1 + 1 == 2);        // passes
Assert(Falsehood);           // ERROR: assertion failed

Halt

Immediately terminates the program.

Halt();

Chronos

Returns the current Unix timestamp in milliseconds.

Potion now is Chronos();
Chant("Timestamp: " + now);

Slumber

Pauses execution for the specified number of milliseconds.

Chant("Casting spell...");
Slumber(2000);  // wait 2 seconds
Chant("Spell complete!");