• Summary
• Acknowledgments
• Getting Started


• Overview of Scheme
• Lexical conventions
• Basic concepts
• Expressions
• Program structure
• Standard procedures


• Haskell Interface


• Standard Libraries
• Husk Libraries
• Standard Feature Identifiers
• Index

Naming conventions

By convention, ? is the final character of the names of procedures that always return a boolean value. Such procedures are called predicates. Predicates are generally understood to be side-effect free, except that they may raise an exception when passed the wrong type of argument.

Similarly, ! is the final character of the names of procedures that store values into previously allocated locations (see section 3.4). Such procedures are called mutation procedures. The value returned by a mutation procedure is unspecified.

By convention, -> appears within the names of procedures that take an object of one type and return an analogous object of another type. For example, list->vector takes a list and returns a vector whose elements are the same as those of the list.

A command is a procedure that does not return useful values to its continuation.

A thunk is a procedure that does not accept arguments.