Fuzion • Fuzion Examples • Rosetta Code Fibonacci Example

Rosetta Code Fibonacci Example

Code Examples

Using Recursion

Code to calculate fibonacci numbers using a recursion:

fib(n i32) i32 =>
  if n < 2 n else fib n-1 + fib n-2

for i in 0..20 do
  say (fib i)

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fib(n i32) i32 =>
  if n < 2 n else fib n-1 + fib n-2
for i in 0..20 do
  say (fib i)
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

Using Loop

Code to calculate fibonacci numbers using a loop:

fib(n i32) =>
  for a := 0, b
      b := 1, next
      next := a + b
      i in 1..n
  else
    a

for i in 0..20 do
  say (fib i)

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fib(n i32) =>
  for a := 0, b
      b := 1, next
      next := a + b
      i in 1..n
  else
    a
for i in 0..20 do
  say (fib i)
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

Using Zip

Code to calculate fibonacci numbers using recursion and a zip:

# idea taken from https://types.pl/web/@pigworker/109679660019147463

# NYI: BUG: type inference fibs => 0 : ()->fibs.zip 1:()->fibs a,b->a+b
fibs list i32 => 0 : ()->(fibs.zip 1:()->fibs a,b->a+b).as_list
fib => fibs[]

for i in 0..20 do
  say (fib i)

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# idea taken from https://types.pl/web/@pigworker/109679660019147463
# NYI: BUG: type inference fibs => 0 : ()->fibs.zip 1:()->fibs a,b->a+b
fibs list i32 => 0 : ()->(fibs.zip 1:()->fibs a,b->a+b).as_list
fib => fibs[]
for i in 0..20 do
  say (fib i)
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

Supporting Negative Fibonacci Numbers

Code to calculate fibonacci numbers including negative ones using a loop:

fib(n i32) =>
  for dir := n.sign    # -1, 0 or +1
      a := 0, b
      b := dir, next
      next := a + b
      i in dir..n : dir
  else
    a

for i in -10..10 do
  say (fib i)

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fib(n i32) =>
  for dir := n.sign    # -1, 0 or +1
      a := 0, b
      b := dir, next
      next := a + b
      i in dir..n : dir
  else
    a
for i in -10..10 do
  say (fib i)
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

last changed: 2025-05-12

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