In the mid-eighties, a number of papers introduced the notion of hygienic macro expansion ( syntax-rules ), a pattern-based system where the syntactic environments of the macro definition and the macro use are distinct, allowing macro definers and users not to worry about inadvertent variable capture ( cf . referential transparency ).
12.
The originating machine invokes a preprocessor to handle header files, preprocessing directives ( such as # ifdef ) and the source files and sends the SSH . Remote machines compile those source files without any local dependencies ( such as libraries, header files or macro definitions ) to object files and send them back to the originator for further compilation.
