170 lines
3.9 KiB
Markdown
170 lines
3.9 KiB
Markdown
# Langatator
|
|
|
|
A very basic interpreted imperative programming language.
|
|
|
|
## Background
|
|
|
|
The goal of this project is to create a simple implementation of a BASIC-like language just to learn a few things along the way and practice my C programming skills.
|
|
|
|
No need to do complex things, just to create a simple interpreted language that can be used to do some arithmetics and create for example a number guessing game.
|
|
|
|
I didn't really study how others languages works beforehand, I'm just guessing how I'm implementing things so that I can make mistakes to learn from.
|
|
|
|
## Progress
|
|
|
|
- 2022-04-29 Implementation of a basic evaluator engine to evaluate arithmetic expressions and call functions
|
|
- 2022-05-15 Clear progress being able to use simple while and if though thre are many glitches
|
|
|
|
ToDo List:
|
|
|
|
- [X] pow operator
|
|
- [X] binary operators
|
|
- [X] implement basic math functions
|
|
- [X] implement random_int(min, max)
|
|
- [X] implement print_number(message)
|
|
- [X] add unit tests
|
|
- [X] allow to set variables
|
|
- [X] read line comments
|
|
- [X] add modulus operator '%'
|
|
- [X] add input_number() std function
|
|
- [X] add NULL type (dirty way to handle no returns and some errors)
|
|
- [X] add type() std function and others type checking functions
|
|
- [X] add ceil() and floor() std functions
|
|
- [X] base of the CLI
|
|
- [X] read a file
|
|
- [X] if statements
|
|
- [X] while statements (with break and continue)
|
|
|
|
- [ ] add multiple characters operators
|
|
- [ ] add inclusive operators like '!=', '>=', '<='
|
|
- [ ] add functions support
|
|
- [ ] add priority operators
|
|
- [ ] add multiline expressions
|
|
- [ ] add short hand if without 'end'
|
|
- [ ] add repeat statement
|
|
- [ ] add static string support (just for ui)
|
|
- [ ] add print_string function
|
|
- [ ] add basic number list support
|
|
- [ ] add fully features strings support
|
|
- [ ] add function to access to environment variables
|
|
|
|
- [ ] add REPL environment
|
|
- [ ] evaluate expression from stdin
|
|
- [X] add config header file
|
|
- [X] ability to modify keywords and customize the lang
|
|
- [ ] add more config options
|
|
|
|
- [ ] add [classic problem solving](https://rosettacode.org) with code examples
|
|
- [ ] add Web Assembly support and publish a demo website
|
|
|
|
- [ ] refactor: use malloc for list
|
|
- [ ] refactor: remove inconsistency on how functions returns error codes
|
|
|
|
## Installation
|
|
|
|
You will need to compile the code from source.
|
|
|
|
- Clone this repository
|
|
- Then compile (eg. with `make`)
|
|
|
|
I use GNU Make with GCC, but I'm sure you can use any C compilers though you may need to edit some part of the code to cope with other compilers (eg. binary constants).
|
|
|
|
## Unit testing
|
|
|
|
I try to have some sort of code coverage, you can run the unit tests by issuing `make test`
|
|
|
|
## The language
|
|
|
|
You would be able to use the lang directly via CLI, via a REPL or by writing in a file (file ext `.ltor`).
|
|
|
|
One instruction set per line.
|
|
|
|
### Comments
|
|
|
|
Can only use single line comments with `#`
|
|
|
|
```
|
|
# this is a comment
|
|
```
|
|
|
|
### Data types
|
|
|
|
To begin with and order to simplify things we would only have numbers as datatypes.
|
|
|
|
When a variable is declared it can be 32 bit integer or 32 bit float.
|
|
|
|
The language may support strings literals in the future.
|
|
|
|
### Expression evaluation
|
|
|
|
function calls: func(arg_a, arg_b)
|
|
operators: +, *, /, ^, %, =, <, >, &, |, !
|
|
|
|
### Set a variable
|
|
|
|
```
|
|
set {VARNAME} to {EXPRESSION}
|
|
```
|
|
|
|
### Evaluate an expression without using the result
|
|
|
|
```
|
|
print_number(42)
|
|
```
|
|
|
|
### function definition
|
|
|
|
```
|
|
function {NAME} do
|
|
...
|
|
end
|
|
```
|
|
|
|
### Conditional structure
|
|
|
|
```
|
|
if {EXPRESSION} then
|
|
...
|
|
end
|
|
```
|
|
|
|
### Conditional loop
|
|
|
|
```
|
|
while {EXPRESSION} do
|
|
...
|
|
end
|
|
```
|
|
|
|
### Unconditional loop
|
|
|
|
```
|
|
repeat {INT EXPRESSION} do
|
|
...
|
|
end
|
|
```
|
|
|
|
```
|
|
repeat i from {INT EXPRESSION} to {INT EXPRESSION} do
|
|
...
|
|
end
|
|
```
|
|
|
|
### std functions
|
|
|
|
```
|
|
abs(nb)
|
|
sqrt,sin,cos,exp,ln,log etc.
|
|
print_number(nb)
|
|
input_number()
|
|
ceil(nb)
|
|
floor(nb)
|
|
random_int(min, max)
|
|
random_float(min, max)
|
|
type(var) -> return the type of a var as int
|
|
is_null(var)
|
|
is_number(var)
|
|
print_string(str)
|
|
print_newline()
|
|
print_ascii(nb)
|
|
```
|