If you need guidance on how to use the compiler and the Real-Time Engine see “Compile and Run Your First Program”, which is a short tutorial on writing applications in Emojicode.
The Language Reference & Guide
- The Basics
- Control Flow
- The s package
- Classes & Value Types
- Inheritance and Overriding
- Types and Namespaces
- Error Handling
- Memory Management
- Appendix I: The Emojicode Compiler
Emojicode is a language that aims to provide the most modern and powerful features to make it easy, fast and fun to write programs. These powerful features include classes, optionals, which can handle the absence of a value, generics, closures and much more.
Emojicode is a strongly typed language, which means that the compiler will verify that all of your operations are correct. This, for instance, prevents you from treating a number as a list of texts.
Although Emojicode only uses Emojis to express the program’s structure, it is similar to programming languages you might know, like C.
Emojicode was designed to allow the development of platform independent applications by running them inside a virtual machine. Your code is first compiled to bytecode by a compiler and can then be executed. The reference implementation of such a virtual machine is called Emojicode Real-Time and can, as the name suggests, execute your code rather fast.
You can include non-executable text in your code by marking it as a comment. Comments begin with 👴 and end at the line break.
👴 This comment ends at the end of the line. Exactly here
Multiline comments starts with 👵 and ends with 👵 and can contain line breaks.
👵 This is a multiline comment. You can even make line breaks. 👵
The 🏁 block
Emojicode needs to know what your program should do when it starts, therefore it requires you to provide a 🏁 block. Here’s an example of a 🏁 block.
🏁 🍇 👴 Get things up and running here... 🍉
The 🏁 block can also return an integer which is then used as the exit code:
🏁 ➡️ 🚂 🍇 👴 Get things up and running here... 🍎 0 👴 Return a code here. 🍉
It occurs at the document level of a document.
When to use Emojis?
There’s sometimes confusion when emojis are used. Basically it’s very simple:
All type, method and initializer names are emojis. On the other hand variables cannot include emojis but must be any combination of characters that cannot be confused with numbers.
Variables pair a name, the variable name, with a value. The variable name can consist of any sequence of characters but may not contain spaces or emojis and may not begin with a number.
There are two types of variables: normal variables and frozen variables. Frozen variables differ from normal ones in that they cannot be changed after they were initially set.
🍦 Declaring a Frozen Variable
The easiest way to declare and set a frozen variable at once is to use 🍦.
🍦 daysInDecember 31 🍦 approximationOf𝜋 3.14159265359
The above code sets the variable
3.14159265359. These variables were declared as frozen variables as they never change.
The compiler infers the type of the variables from the values given.
🍮 Setting and Declaring a Variable
To declare or change a normal, changeable variable you should use 🍮. If the variable you want to set is already declared its value will be changed, given that it is not frozen; in that particular case an error message would be emitted. Otherwise the variable is declared in the current scope.
🍮 moneyLeft 20 🍮 numberOfTimes“SmokeOnTheWater”WasPlayed 20348292837483929
These variables were justifiably declared as changeable variables because they obviously change often. You should however always prefer frozen variables if you don’t intend to modify the variable.
🍮 can also be used directly followed by an emoji, which is a special use and called assignment by call. Assignment by call is described in Classes & Value Types.
🍰 Declaring Variables
You can declare a variable yourself regardless if a variable with the same name was declared in the parent scope but you may not declare a variable more than one time.
🍰 variableName variableType
variableName must be a valid variable name. variableValue may be an expression of any type.
After you declared the variable in the local scope you can use 🍮 to set it to a value. The compiler will throw an error if you try to access an uninitialized variable. Optionals are automatically initialized to Nothingness.
Beware of that 🍰 can shadow variables from parent scopes and can, for example, make instance variables inaccessible.
Variables are only accessible from the scope in which they were declared. Every code block (everything between a 🍇 and 🍉) defines a separate scope, which disappears once the block was executed:
🏁 🍇 🍦 work 🔤Work It Harder Make It Better🔤 🍊 👍 🍇 😀 work 👴 work is accessible here 🍦 doIt 🔤Do It Faster, Makes Us stronger🔤 🍉 😀 work 👴 work still works, of course 😀 doIt 👴 doIt is no longer accessible here 🍉
You cannot access scopes beyond the method or initializer from your code. Nevertheless, you can access the object scope in instance methods and initializers. Closures are also considered an exception from this rule. You’ll learn more about these two kinds for special scoping in Classes & Value Types and Callables.
Integer literals can be written in
- Decimal notation, like
- Hexadecimal notation, with the prefix
- Octal notation, with the prefix
You can use
_ within integer literals to improve readability:
. can be used as decimal separator to create a 🚀.
There are only two numeric types in Emojicode:
- 🚂 can represent any integer in the interval [-263+1, 263-1].
- 🚀 can be used to store a real number with the common limitations. Read this Wikipedia article for more information.
Emojicode has a type to represent Boolean values: 👌. A boolean value can either be true or false. A true value is created using 👍 and a false value is created using 👎.
In the example below two variables are set to a boolean value.
🍦 emojicodeIsTheFunniestLanguage 👍 🍦 phpIsAsCool 👎
A Symbol is a single Unicode character represented by the symbol type 🔣. The symbol type can represent any character defined in Unicode.
You can include the symbol in the source code file by prepending 🔟 before the desired symbol. This is called a Symbol literal.
🍦 percent 🔟%
Including Other Source Code Files
An Emojicode program is always compiled from a single file. Nevertheless, you can include other source code files. Basically, this just inserts the code from the file at the point where you included it.
string must be a string whose value is a path to another Emojicode source file. The path is relative to the directory which included the document with the 📜 statement.
Do not use this method to share code across projects. If you have written really fancy code, create a package, which you can easily make available to other people.