— Scheme Procedure: id x
— Scheme Procedure: identity x

Return x.

— Scheme Procedure: 1+ n

Return one added to n.

— Scheme Procedure: 1- n
— Scheme Procedure: -1+ n

Return one subtracted from n.

— Scheme Procedure: return-it [args...]

Return the first element in args, or #f if there are none.

— Scheme Procedure: and=> value procedure

If value is non-#f, call procedure passing it value.

— Scheme Procedure: apply-to-args args proc

Apply proc to args, a list.

— Scheme Procedure: in-vicinity vicinity file

Return a filename composed of vicinity and file. vicinity need not end with trailing slash.

— Scheme Macro: false-if-exception expr [rest...]

Evaluate the sequence expr rest..., catching any errors. If there are no errors, return the value of the last evaluated expression. Otherwise, return #f.

— Scheme Procedure: symbol-append [symbols...]

Return a symbol whose name is formed by appending the names of symbols.

— Scheme Procedure: list->symbol chars

Return a symbol whose name is composed of chars, a list of characters.

— Scheme Procedure: obarray-symbol-append ob [symbols...]

Return a symbol in obarray ob whose name is formed by appending the names of symbols.

— Scheme Procedure: obarray-gensym obarray [opt]

Like gensym but for obarray.

— Scheme Macro: collect [forms...]

Return a list of the results of all constituent forms. Contrast this with begin, which returns the result of the last form, only.