Version: 5.1.3
MzScheme: Legacy Language
The mzscheme language provides nearly the same
bindings as the mzscheme module of PLT Scheme
version 372 and earlier.
Unlike version 372, the mzscheme language does not include set-car! or set-cdr!, and cons makes immutable pairs, as in scheme/base; those changes make modules built on mzscheme reasonably compatible with modules built on scheme/base.
Otherwise, the mzscheme language shares many bindings with scheme/base. It renames a few bindings, such as syntax-object->datum instead of syntax->datum, and it provides old versions of some syntactic forms, such as lambda without support for keyword and optional arguments.