Phase 3 — Functions
Phase 3 — Functions
Goals for this phase, and a full JS/TS → Python cheat sheet
Estimated time: ~1 hour.
Goals
By the end of this phase you should be comfortable with:
- parameters
return- default parameters
- keyword arguments
- type hints
*args**kwargsbasics
Type hints are especially important here — FastAPI reads them to validate requests and generate docs automatically, so getting comfortable with them now pays off later.
Each topic is its own page in the sidebar, taught with a JS/TS → Python comparison, followed by a small example.
Cheat sheet
JavaScript / TypeScript Python
────────────────────────────────────────────────────────────
function add(a, b) { def add(a, b):
return a + b; return a + b
}
function add(a = 1) { } def add(a=1):
function add(...rest) { } def add(*args):
function add({ ...obj }) { } def add(**kwargs):
function add(a: number, b: number): number { def add(a: int, b: int) -> int:
return a + b; return a + b
}