assistance-engine/docs/developer.avapframework.com/chapter9_44.md

Literal Patterns

In AVAP, literal patterns are used to match specific literal values, such as numbers, strings, or boolean values. The syntax for a literal pattern is:

literal_pattern ::=  signed_number
                     | strings
                     | "None"
                     | "True"
                     | "False"

A literal pattern only succeeds if the value of the subject is equal to the specified literal value.

Here are examples of literal patterns and their usage:

match value:
    case 42:
        print("Matched the number 42")
    case "hello":
        print("Matched the string 'hello'")
    case None:
        print("Matched None")
    case True:
        print("Matched True")
    case False:
        print("Matched False")
    case _:
        print("No match")

In this example:

• case 42: matches if value is exactly 42.
• case "hello": matches if value is the string "hello".
• case None: matches if value is None .
• case True: matches if value is True .
• case False: matches if value is False .
• case _: is a catch-all pattern that executes if none of the previous patterns match.

Literal patterns are useful for matching specific, known values and are a fundamental part of pattern matching in AVAP.