# 036: Function Composition
# Combine functions to create new ones

# Simple functions
add_one = (x) => x + 1
double = (x) => x * 2
square = (x) => x * x

# Manual composition
result = square(double(add_one(3)))
show result  # (3+1)*2 = 8, 8*8 = 64

# Compose helper
compose(f, g):
  return (x) => f(g(x))

# Create composed function
double_then_square = compose(square, double)
show double_then_square(5)  # (5*2)^2 = 100

# Chain multiple operations
numbers = [1, 2, 3, 4, 5]

result = numbers
  .map((x) => x * 2)      # double each
  .filter((x) => x > 5)   # keep if > 5
  .reduce((sum, x) => sum + x, 0)  # sum all

show result  # 6 + 8 + 10 = 24