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#%app

3.5 Function Calls

(id expr expr ...)
A function call in Intermediate is the same as a Beginning function call, except that it can also call locally defined functions or functions passed as arguments. That is, id can be a function defined in local or an argument name while in a function.

(#%app id expr expr ...)
A function call can be written with #%app, though it’s practically never written that way.