Core syntax Control flow

Statements and Control Flow

Klyn uses indentation-defined blocks and a compact statement vocabulary. This page covers the control-flow statements you will use constantly in real code.

Assignment

count = 10
name as String = "Ada"
count += 1
count--

Assignment updates an existing variable while preserving its established type.

If, Elif, Else

score = 72
if score >= 90:
    print("excellent")
elif score >= 50:
    print("pass")
else:
    print("retry")

While Loops

i = 0
while i < 3:
    print(i)
    i += 1

Use while when the continuation condition depends on values updated in the body.

Range Loops

for i = 0 to 5:
    print(i)

Both bounds are inclusive. The example prints 0 through 5. When iterating over indices, use an explicit upper bound such as values.size - 1.

Collection Iteration

for value in [10, 20, 30]:
    print(value)

config = {"theme": "dark", "fullscreen": true}

for key in config:
    print(key)

for pair in config.items():
    print(pair)

Iterating directly over a map yields keys. Use keys(), values(), or items() when you want a specific view.

Break and Continue

while true:
    text = input("> ")
    if text == "":
        continue
    if text == "quit":
        break
    print(text)

Assert and Pass

assert count > 0

if featurePending:
    pass

assert is appropriate for invariants and tests. pass is an explicit placeholder that leaves a block intentionally empty.