declaration/definition
declare function-library string-expression
Sets the default function library for any following external function definition that does not have an "in function-library" part. More than one declare function-library declaration can appear in a program. If more than one is used, each declare function-library declaration applies to the function definitions that follow until another declare function-library declaration is encountered. This is consistent with all OmniMark library calls.
The "in function-library" part of an external function can be omitted only if the definition is preceded by a declare function-library declaration. There is no "built-in" or "system-supplied" default external function library.