Function alternate_case 

pub fn alternate_case(input: &str) -> String

Alternates between uppercase and lowercase for each alphabetic character.

Creates a predictable pattern starting with uppercase, then lowercase, and repeating for each letter. Non-alphabetic characters don’t affect the pattern. This is also known as “spongebob case” or “mocking case”.

Use Cases

• Testing: Verify case-insensitive string comparisons
• Visual: Create distinctive formatting for emphasis or mockery
• Red Team: Test filter bypass with alternating patterns

Examples

use redstr::alternate_case;

assert_eq!(alternate_case("hello"), "HeLlO");
assert_eq!(alternate_case("hello world"), "HeLlO wOrLd");

// Non-alphabetic characters are preserved but don't affect the pattern
assert_eq!(alternate_case("a1b2c3"), "A1b2C3");