Toy v2 Quick-Start Guide

To help you start using Toy as fast as possible, here are the most useful elements of the language. Not everything available is listed, but this should let you start coding right away.

Keyword ‘print’

The print keyword takes one value as a parameter, which is sent to stdout by default, or can be redirected elsewhere using the output C API.

print "Hello World!";

Keyword ‘assert’

The assert keyword takes two values as parameters, separated by a comma. If the first value is falsy or null, the optional second parameter is sent to stderr by default, or can be redirected elsewhere using the output C API. If no second parameter is provided, a generic message is used instead.

An option to disable the assert keyword during compilation is provided in the parser C API.

//nothing happens
assert 1 < 2;

//this assert will fail, and output the second parameter
assert null, "Hello world!";

Variables and Types

Values can be stored in variables, by specifying a name with the var keyword. The name can be declared with an optional type, which restricts the type of value that can be stored in the name. If no type is specified, any is used instead.

var answer = 42;

var question: string = "How many roads must a man walk down?";

To make a variable immutable, you can add the const keyword after the type when it’s declared. If you do, it must be assigned a value.

var quote: string const = "War. War never changes.";

The types available in Toy are:

type name description
bool boolean Either true or false.
int integer Any whole number (32-bits).
float float A decimal number (32-bits), using floating-point arithmetic.
string string A piece of text, supports UTF-8, in theory.
array array A series of values stored sequentially in memory.
table table A series key-value pairs stored in such a way that allows for fast lookups. Booleans, functions, opaques and null can’t be used as keys.
function function A chunk of reusable code that takes zero or more parameters, and returns zero or more results. Functions are declared with the fn keyword.
opaque opaque This value is unusable in the script, but can be passed from one imported function to another.
any any The default type when nothing is specified. Theis can hold any value.

Note: Arrays, tables, functions and opaques are not fully implemented at the time of writing, so details may change.

Control Flow

Choosing an option, or repeating a chunk of code multiple times, is essential for any general purpose language.

Choosing between two options can be done with the if-then-else else statement. If the condition is truthy, the ‘then-branch’ will be executed. Otherwise, the optional ‘else-branch’ is executed instead.

var answer = 42;

if (answer < 56) {
    print "Cod dang it!";
}
else {
    print "Something's fishy here...";
}

var challenge = "hard";

if (challenge == "hard") {
    print "I choose to build a scripting language, not because it's easy, but because it's hard!";
}

//the else-branch is optional

To repeat a certain action, use the while-then loop, which repeats the body as long as the condition is true at the beginning of each loop.

var loops = 0;

while (loops++ < 8) {
    print "These episodes are endless.";
}

To break out of a loop, you can use the break keyword. Alternatively, to restart the loop early, use the continue keyword.

var loops = 0;

while (true) {
    if (++loops < 15532) {
        continue;
    }

    break; //poor yuki ;_;
}

Note: The for loop is coming, eventually, but isn’t vital right now.

Arrays and Tables

Watch this space.

Functions

Watch this space.

External Libraries and Extending Toy

Watch this space.

Reserved Keywords & Operators

Watch this space.

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