Created
September 25, 2023 06:03
-
-
Save ballerina-github-bot/03b42e463700fc3e1a0d0ff0c32aa964 to your computer and use it in GitHub Desktop.
examples/constraint-validations
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
import ballerina/constraint; | |
// Constraint on the `int` type. | |
@constraint:Int { | |
minValue: 18 | |
} | |
type Age int; | |
type Student record {| | |
// Constraint on the `string`-typed record field. | |
@constraint:String { | |
pattern: re`[0-9]{6}[A-Z|a-z]` | |
} | |
string id; | |
string name; | |
// Constrained type used as a record field. | |
Age age; | |
// Constraint on the `string[]`-typed record field. | |
@constraint:Array { | |
minLength: 1, | |
maxLength: 10 | |
} | |
string[] subjects; | |
|}; | |
public function main() returns error? { | |
Student student = { | |
id: "200146B", | |
name: "David John", | |
age: 25, | |
subjects: ["Maths", "Science", "English"] | |
}; | |
// To validate the constraints on the `Student` record, the `validate` function should be | |
// called explicitly. If the validation is successful, then, this function returns the type | |
// descriptor of the value that is validated. | |
student = check constraint:validate(student); | |
// Set the student's age to 17, which will violate the `minValue` constraint on `Age`. | |
student.age = 17; | |
// When the validation fails, the `validate` function returns a `constraint:Error`. | |
student = check constraint:validate(student); | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment