Add oneOf, anyOf validations

src/commonMain/kotlin/io/konform/validation/types/ValidateAll.kt

@@ -22,6 +22,7 @@ public class ValidateAll<T>(
     override fun toString(): String = "ValidateAll(validation=$validations)"
 }
 
+/** Validation that runs multiple validations in sequence and returns all validation errors. */
 public class FailFastValidation<T>(
     private val validations: List<Validation<T>>,
 ) : Validation<T> {

src/commonMain/kotlin/io/konform/validation/types/ValidationAny.kt

@@ -0,0 +1,34 @@
+package io.konform.validation.types
+
+import io.konform.validation.Invalid
+import io.konform.validation.Valid
+import io.konform.validation.Validation
+import io.konform.validation.ValidationResult
+import io.konform.validation.flattenNotEmpty
+import io.konform.validation.flattenOrValid
+
+public class ValidationAny<T>(
+    private val validations: List<Validation<T>>,
+    private val aggregateInvalidResults: (List<Invalid>) -> Invalid = List<Invalid>::flattenNotEmpty,
+) : Validation<T> {
+    override fun validate(value: T): ValidationResult<T> {
+        val errors = mutableListOf<Invalid>()
+        for (validation in validations) {
+            when (val result = validation.validate(value)) {
+                // We only need 1 validation to succeed the "any" validation
+                is Valid -> return result
+                is Invalid -> errors + result
+            }
+        }
+        return errors.flattenOrValid(value)
+    }
+
+    override fun toString(): String = "ValidationAny(validation=$validations)"
+
+    private companion object {
+        private fun defaultAggregateInvalidResults(invalids: List<Invalid>): Invalid {
+            val combinedErrors =
+                "all validations failed: ${invalids.flatMap { invalid -> invalid.errors.map { it.message } }}"
+        }
+    }
+}

src/commonTest/kotlin/io/konform/validation/validationbuilder/ValidateAnyTest.kt

@@ -0,0 +1,26 @@
+package io.konform.validation.validationbuilder
+
+import io.konform.validation.Validation
+import io.konform.validation.constraints.maxLength
+import io.konform.validation.constraints.minLength
+import kotlin.test.Test
+
+class ValidateAnyTest {
+    @Test
+    fun validateAny() {
+        val validation =
+            Validation<String> {
+                oneOf(
+                    "must be either length 5 or 10",
+                    {
+                        minLength(5)
+                        maxLength(5)
+                    },
+                    {
+                        minLength(10)
+                        maxLength(10)
+                    },
+                )
+            }
+    }
+}