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Source for wiki EvalDefine version 2

author

cowan

comment

ipnr

198.185.18.207

name

EvalDefine

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text

Passing a definition to `eval` may or may  not work according to R5RS.  Furthermore, in many Schemes, but not in R5RS, it's possible to call `eval` with just one argument, implying the interaction environment.  I tested the suite of Schemes to determine whether and how it's possible to add definitions to the interaction environment by evaluating the following four forms at the REPL:

{{{
(eval '(define x 32) (interaction-environment))
x
(eval '(define y 55))
y
}}}

The following Schemes allow definition by `eval`:

 * Supports both `interaction-environment` and single-argument `eval`: Gambit, Chicken, Bigloo, Kawa, SISC, SCM, Chez, Larceny, NexJ, STklos, !TinyScheme, Sizzle, Spark

 * Supports single-argument `eval` but not `interaction-environment`: Racket, RScheme, Scheme 7, XLisp, Rep, Elk, UMB, VX, Llava, SXM, !FemtoLisp, Inlab (SXM provides `interaction-environment` but calling it signals an error)

 * Supports `interaction-environment` but not single-argument `eval`: Gauche, Scheme48/scsh, Guile, Vicare, Ypsilon, !IronScheme, !SigScheme, Dream, BDC

The following Schemes do ''not'' allow definition by `eval`:

 * Does not support `interaction-environment` or single-argument `eval`: MIT, Mosh, KSi, Oaklisp, Dfsch, Owl Lisp

 * Supports both `interaction-environment` and single-argument `eval`, but definitions aren't visible in the interaction environment: Chibi

 * Supports `interaction-environment` but not single-argument `eval`, but definitions aren't visible in the interaction environment: Shoe

 * Does not support `eval` at all: Scheme 9, Schemik

time

2012-06-27 09:24:28