Comparación y Lógica

Igualdad, orden, floats (IEEE-754), cadenas y arrays — todos devuelven bool.

// Feature: Comparison operators

// Syntax: `==`, `!=`, `<`, `<=`, `>`, `>=`

// When to use: comparing values. Always return `bool`. In Zolo,

// `==` compares by value for primitive types and structurally for

// structs/arrays (deep equality).


// Equality and inequality.

print(1 == 1)  // true

print(1 == 2)  // false

print(1 != 2)  // true

print("alice" == "alice")  // true

print("alice" != "bob")  // true


// Order.

print(3 > 2)  // true

print(3 >= 3)  // true

print(1 < 5)  // true

print(1 <= 1)  // true


// Floats.

print(1.5 < 1.6)  // true

print(0.1 + 0.2 == 0.3)  // false (IEEE-754!)


// Strings — lexicographic comparison.

print("apple" < "banana")  // true

print("Z" < "a")  // true (ASCII: Z=90, a=97)


// Arrays — structural comparison.

print([1, 2, 3] == [1, 2, 3])  // true

print([1, 2, 3] == [1, 2, 4])  // false


// Chaining via `&&` (Zolo does NOT support `a < b < c` like Python).

let n = 5
print(0 < n && n < 10)  // true

Cortocircuito demostrado con una función con efecto secundario y precedencia entre !, && y ||.

// Feature: Logical operators

// Syntax: `&&` (and), `||` (or), `!` (not)

// When to use: combine booleans in conditionals. `&&` and `||`

// short-circuit (the 2nd expression is NOT evaluated if the 1st

// already decides). `!` flips a bool.


// AND — true only if both are true.

print(true && true)  // true

print(true && false)  // false

print(false && true)  // false


// OR — true if at least one is true.

print(true || false)  // true

print(false || false)  // false


// NOT — flips.

print(!true)  // false

print(!false)  // true

print(!(1 == 2))  // true


// Short-circuit: `||` stops on the first true.

fn side_effect(name: str) -> bool {
  print("evaluated: {name}")
  return true
}

let _r = true || side_effect("right")  // "right" is NEVER evaluated

print("---")

// `&&` stops on the first false.

let _r2 = false && side_effect("right")  // "right" is NOT evaluated

print("---")

// Precedence: `!` > `&&` > `||`.

print(true || false && false)  // true (= true || (false && false))

print(!true || true)  // true (= (!true) || true)


// Combining with comparisons.

let age = 25
let has_id = true
print(age >= 18 && has_id)  // true

print(age < 13 || age > 65)  // false