The Current REPL Environment (MIT/GNU Scheme 12.0.90)

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#### 3.1.4 The Current REPL Environment

Every REPL has a current environment, which is the place where expressions are evaluated and definitions are stored. When Scheme is started, this environment is the value of the variable `user-initial-environment`. There are a number of other environments in the system, for example `system-global-environment`, where the runtime system’s bindings are stored.

You can get the current REPL environment by evaluating

    (nearest-repl/environment)

There are several other ways to obtain environments. For example, if you have a procedure object, you can get a pointer to the environment in which it was closed by evaluating

    (procedure-environment procedure)

Here are some procedures that manage the REPL’s environment:

procedure: ge environment ¶

  Changes the current REPL environment to be environment (`ge` stands for “Goto Environment”). Environment is allowed to be a procedure as well as an environment object. If it is a procedure, then the closing environment of that procedure is used in its place.

procedure: ve environment ¶

  Starts a sub-REPL with it’s environment set to environment (`ve` stands for “Visit Environment”). Environment is allowed to be a procedure as well as an environment object. If it is a procedure, then the closing environment of that procedure is used in its place.

procedure: pe ¶

  This procedure is useful for finding out which environment you are in (`pe` stands for “Print Environment”). If the current REPL environment belongs to a package, then `pe` returns the package name (a list of symbols). If the current REPL environment does not belong to a package then the environment is returned.

Next: REPL Escapes, Previous: Restarting, Up: The Read-Eval-Print Loop [Contents][Index]