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The compile() function is Porffor’s main compiler API that transforms JavaScript code into WebAssembly.

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Function Signature

compile(source: string, module?: boolean, print?: (str: string) => void)
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source
string
required
JavaScript source code to compile
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module
boolean
default:"false"
Whether the source should be treated as a module. When true, enables module features like import/export. Defaults to script mode.
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print
function
default:"process.stdout.write"
Function to use for printing output (used by console.log, etc). Receives a string argument.Default: str => process.stdout.write(str)

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Return Value

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exports
object
Object containing exported functions from the compiled code. Each function returns the JavaScript representation of Porffor values.
  • main - The main entry point (renamed from m)
  • $ - WebAssembly memory instance
  • Other named exports from the source code
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wasm
Uint8Array
Raw WebAssembly binary (Wasm bytecode)
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times
number[]
Array of compilation timing metrics:
  • [0] - Compilation time in milliseconds
  • [1] - Instantiation time in milliseconds
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pages
number
Number of WebAssembly memory pages allocated
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c
string
Generated C code (only when using C target)

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Usage

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Basic Compilation

import compile from 'porffor';

const { exports } = compile(`
  export const add = (a, b) => a + b;
`, true);

console.log(exports.add(2, 3)); // 5

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Script Mode

const { exports, wasm } = compile(`
  function factorial(n) {
    return n <= 1 ? 1 : n * factorial(n - 1);
  }
  factorial(5);
`);

const result = exports.main();
console.log(result); // 120

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Custom Print Function

const output = [];
const { exports } = compile(
  `console.log('Hello, Porffor!');`,
  false,
  str => output.push(str)
);

exports.main();
console.log(output); // ['Hello, Porffor!']

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Accessing Compilation Metrics

const { times, pages, wasm } = compile(source, true);

console.log(`Compiled in ${times[0].toFixed(2)}ms`);
console.log(`Instantiated in ${times[1].toFixed(2)}ms`);
console.log(`Memory pages: ${pages}`);
console.log(`Binary size: ${wasm.length} bytes`);

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Advanced Usage

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Compiling from Existing AST

You can also pass a pre-compiled object instead of source code: 
const compiled = compile(source, true);
// Later, re-instantiate with the same compiled output
const { exports } = compile(compiled);

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Exception Handling

The compiled functions throw JavaScript exceptions that match the behavior of the original code: 
const { exports } = compile(`
  export const divide = (a, b) => {
    if (b === 0) throw new Error('Division by zero');
    return a / b;
  };
`, true);

try {
  exports.divide(10, 0);
} catch (e) {
  console.error(e.message); // "Division by zero"
}

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Performance Notes

  • Compilation happens at runtime and may take time for large codebases
  • The times array provides metrics for profiling
  • Set Prefs.profileCompiler = true for detailed compilation logging
  • Use Prefs.disassemble = true to get WebAssembly disassembly output

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See Also

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