Temil

(tree-evaluated expression, minimally interpreted language)

Temil is a small interpreted and purely expression based programming language.

Introduction

The main idea is to give controlled acess to execution functionality.

In concept, Temil is just a definition of how to structure expressions, everything else is up to you. Although, for convenience, a lexer, a parser and the entrypoint for execution is provided.

EBNF

whitespace = " " ;
operator = STRING ;
literal = [ "'" ], STRING, [ "'" ];
expression = "(", ( operator, { expression | literal } ), ")" ;

Expressions

Expressions are Temils way of execution. Everything in Temil is an expression composed of an operator and a list of arguments, which may either be expressions or literals.

Literals

Literals are a way of giving temil a "literal" value to work with. Everything written in between single quotation marks is considered top be a literal. By default temil knows what literals are, but does not know what to do with them. For that you'll need operators.

Operators

Operators define the execution of your Temil Interpreter. By default there are no operators, so you'll have to write your own.

Example

For this example we have two operators defined:

• and is an operator that takes two expressions, evaluates them, expects the evaluated values to be numbers and then adds them together.
• num is an operator that parses a temil literal and turns it into the host languages representation of a number.

(add (num '1') (num '2'))

The result of this expression is the number 3 in the host languages representation of a number.