Can a property have multiple @pattern decorators?

[nkiesel]

JSON schema allows to use allOf or anyOf for patterns, e.g.

lastName:
    type: string
    allOf:
      - pattern: ^[A-Za-z '-]{1,30}$
      - pattern: "[^ ]"

to limit the allowed characters, but also to make sure the value contains at least one non-blank character. How do I express this in typespec?

[bterlson]

We don't support emitting multiple patterns via allOf, it's an interesting idea.

As an alternative, you could consider using ^[A-Za-z'\- ]* [A-Za-z'\- ]*$ in combination with @minLength and @maxLength.

It might be tempting to use a lookahead like ^(?=.* )[A-Za-z '-]{1,30}$ which is allowed by JSON schema, but in my opinion it's always better to stick the I-Regexp subset if at all possible.

[nkiesel]

This of course was just a simple example. In reality, I have fields which have 5 different patterns, and also using e.g. case-insensitive patterns and anyOf, allOf, and noneOf.