Patent attributes
The disclosure generally describes computer-implemented methods, software, and systems for enabling dynamic tokens in an expression parser. An example method includes identifying an expression represented as a natural language input for validation by a parser. Each of the phrases in the expression are iteratively converted into a set of tokens by determining whether a current phrase matches a pre-defined token associated with a known grammar rule, and, in response to determining that the current phrase matches a pre-defined token, generating a token for the current phrase for use in validating the expression. If the current phrase does not match a pre-defined token, the unrecognized string of characters is compared to a plurality of dynamic tokens included in an external pool of tokens to generate a generic token of an identified type. The dynamic token is replaced with the generic token and can be used to validate the expression.