LGE - Functional Programming Language Compiler

LGE (Lambda g(e)) is a toy functional programming language compiler that I wrote to try out llvm. 🙂

Language Syntax

Function Definitions

let name: type = (param: type, ...) -> expression

Types

• int: 32-bit integer
• float: 32-bit floating point
• char: 8-bit character
• str: C-style string
• func: Function pointer

Built-in Functions

• str_print(str) -> int: Print string to stdout
• str_read(int) -> str: Read string from stdin (up to n characters)
• str_len(str) -> int: Get length of string
• str_at(str, int) -> char: Get character at index
• str_sub(str, int, int) -> str: Get substring from start to end index
• str_find(str, str) -> int: Find substring (-1 if not found)
• int_to_str(int) -> str: Convert integer to string
• str_to_int(str) -> int: Convert string to integer
• float_to_str(float) -> str: Convert float to string
• str_to_float(str) -> float: Convert string to float
• str_cmp(str) -> int: Returns 1 if true

Comments and Line Continuation

• Comments start with #
• Line continuation with \

Building Prerequisites

• Linux
• CMake 3.20+
• C++20 compatible compiler
• LLVM 18 development libraries
• Git
• python3 (for running tests)

Usage

$> lgec --help
LGE
Usage: lgec [OPTIONS] input_file

Positionals:
  input_file TEXT:FILE REQUIRED
                              Input LGE source file

Options:
  -h,--help                   Print this help message and exit
  --dump-tokens               Dump lexer tokens to stdout
  --dump-ast                  Dump AST to stdout

Basic Compilation

$> ./lgec tests/examples/hello_world.lge | lli -load=liblge_runtime.so
Hello world!

License

This project is licensed under the MIT License - see the MIT License file for details.