import ballerina/io;
type Headers record {
string 'from;
string to;
// Records can have optional fields
string subject?;
};
Headers h = {
'from: "John",
to: "Jill"
};
//Use ?. operator to access optional field
string? subject = h?.subject;
public function main() {
io:println("Header value: ", h);
io:println("Subject value:", subject);
}
Optional FieldsFields of a record can be marked as optional. These fields can be omitted when creating a record.
Such fields can be accessed via optional field access (e.g., |
import ballerina/io;
type Headers record {
string 'from;
string to;
string subject?;
Records can have optional fields
};
Headers h = {
'from: "John",
to: "Jill"
};
string? subject = h?.subject;
Use ?. operator to access optional field
public function main() {
io:println("Header value: ", h);
io:println("Subject value:", subject);
}
bal run optional_fields.bal
Header value: {"from":"John","to":"Jill"}
Subject value:
