[3] RFC 2244 - ACAP -- Application Configuration Access Protocol, , https://tools.ietf.org/html/rfc2244#page-16

[1] RFC 5231 - Sieve Email Filtering: Relational Extension ( 版) https://tools.ietf.org/html/rfc5231#section-3

The "i;ascii-numeric" comparator, as defined in [RFC4790], MUST be

supported for any implementation of this extension. The comparator

"i;ascii-numeric" MUST support at least 32-bit unsigned integers.

Larger integers MAY be supported. Note: the "i;ascii-numeric"

comparator does not support negative numbers.

[2] RFC 5260 - Sieve Email Filtering: Date and Index Extensions () https://tools.ietf.org/html/rfc5260