iterators_comprehensive.ruff

# Iterators and Generators Demo
# Demonstrates the iterator functionality in Ruff

print("=" * 50)
print("ITERATOR DEMONSTRATION")
print("=" * 50)

# Basic array iteration with filter
print("\n1. Filter - Get even numbers")
numbers := [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
even_numbers := numbers.filter(func(n) { return n % 2 == 0 }).collect()
print(even_numbers)  # [2, 4, 6, 8, 10]

# Map transformation
print("\n2. Map - Double all numbers")
doubled := numbers.map(func(n) { return n * 2 }).collect()
print(doubled)  # [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]

# Chaining multiple operations
print("\n3. Chaining - Filter then map")
result := numbers
    .filter(func(n) { return n > 5 })
    .map(func(n) { return n * n })
    .collect()
print(result)  # [36, 49, 64, 81, 100]

# Using take to limit results
print("\n4. Take - Get first 3 items")
first_three := numbers.take(3).collect()
print(first_three)  # [1, 2, 3]

# Complex chaining
print("\n5. Complex chaining - filter, map, and take")
complex_result := numbers
    .filter(func(n) { return n % 2 == 1 })  # Odd numbers
    .map(func(n) { return n * 3 })          # Triple them
    .take(3)                                 # Take first 3
    .collect()
print(complex_result)  # [3, 9, 15]

# String operations
print("\n6. String filtering and transformation")
words := ["hello", "world", "ruff", "programming", "language"]
long_words := words
    .filter(func(w) { return len(w) > 5 })
    .map(func(w) { return to_upper(w) })
    .collect()
print(long_words)  # ["PROGRAMMING", "LANGUAGE"]

# Practical example: data processing pipeline
print("\n7. Practical example - Process scores")
scores := [45, 67, 89, 23, 91, 56, 78, 34, 92, 88]
passing_scores := scores
    .filter(func(s) { return s >= 60 })      # Only passing grades
    .map(func(s) { return s + 5 })           # Curve: add 5 points
    .take(5)                                  # Top 5
    .collect()
print("Top 5 curved passing scores:")
print(passing_scores)

# Custom predicate functions
print("\n8. Using stored functions")
is_positive := func(n) { return n > 0 }
square := func(n) { return n * n }

mixed_numbers := [-5, 3, -2, 7, -1, 9]
result := mixed_numbers
    .filter(is_positive)
    .map(square)
    .collect()
print("Positive numbers squared:")
print(result)  # [9, 49, 81]

print("\n" + "=" * 50)
print("All iterator demonstrations completed!")
print("=" * 50)