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Re: [Scm-discuss] eval couldn't bind local variable?
|
From: |
Aubrey Jaffer |
|
Subject: |
Re: [Scm-discuss] eval couldn't bind local variable? |
|
Date: |
Sun, 03 Apr 2011 12:12:36 -0400 (EDT) |
| From: Tom Kwong <address@hidden>
| Date: Sat, 2 Apr 2011 17:57:57 -0700
|
| I'm new to scheme but is puzzled by the following behavior. Can
| someone help explain what's going on here?
|
| (letrec ((x 0)) (eval 'x))
| => unbound variable: x
|
| (define a 3)
| (letrec ((x 0)) (eval 'a))
| => 3
EVAL evaluates its argument in the top-level environment.
LETREC establishes a local environment for x which the call to EVAL
doesn't see.