Pepper is an interpreted programming toy language that I wrote with a focus on simplicity and verbosity. It is dynamically typed and comes with built-in garbage collection. At the moment, it's basically a weird hybrid between C, JavaScript and Python.
It's also quite fast for an interpreted language that does not (yet) use JIT compilation.
Pepper is implemented in C11 with no external dependencies. It would have been ANSI standard if it weren't for the use of computed goto's in the VM main loop to improve CPU branch prediction.
// Variable declarations
let a = 5;
let b = 25;
// Reassign (previously declared) variables
a = a * 5;
// For loops
for (let i = 0; i < 10; i++) {
// i = 0 .. 9
}
// While loops
while (b > a) {
b = b - 5;
break;
}
// If statements
if (b == a || a == b) {
print("b equals a!");
}
// Strings
let c = "Hello world";
c = str_split(c, " ");
type(c); // "ARRAY"
len(c); // 2
// Arrays
let d = [5, true, "Pepper"];
d[0]; // 5
array_push(d, 10);
array_pop(d); // 10
// Slices
let s = d[0:2]; // [5, true]
// Functions
let fibonacci = fn(x) {
if (x < 2) {
return x;
}
return fibonacci(x - 1) + fibonacci(x - 2);
}
// Built-in functions
print("35th fibonacci number is: ", fibonacci(35));
print("Type of c = ", type(c));
print("Length of c = ", len(c));
print("Integer value of true = ", int(true));
file_get_contents("file.txt"); More examples can be found in the examples directory.
Build Pepper interpreter (and REPL)
make
Launch the REPL
bin/pepper
Interpret a Pepper script:
bin/pepper examples/arithmetic.pr
Build & run tests
make check
A benchmark to calculate the 35th fibonacci number using a recursive function is run on every commit through this Github action workflow.
For fun, I ran the same algorithm expressed in some other interpreted languages on the same hardware (my laptop). This is how Pepper compares:
| Language | fib-35 | string-concat-count | selection-sort |
|---|---|---|---|
| Pepper | 0.698 | 0.024 | 0.349 |
| Lua 5.4 | 0.830 | 0.030 | 0.156 |
| Node 15 | 0.210 | 0.058 | 0.071 |
| PHP 8.0 | 0.480 | 0.036 | 0.595 |
| PHP 5.6 | 2.720 | ||
| Pypy 7.3 | 0.240 | 0.154 | 0.192 |
| Python 3.9 | 1.910 | 0.060 | 1.009 |
| Ruby 3.0 | 0.800 | 0.102 | 0.877 |
MIT licensed.