Version 2.7 update

[johnsondavies]

Earlier this month I released uLisp Version 2.7 on all platforms, which changed uLisp from using Dynamic Scoping to using Lexical Scoping; I wrote about the benefits of this in an earlier post:

Version 2.7 released

Here’s a simpler explanation of the scoping test I gave in my first post. We define a function f which uses a free variable, lex. The value of lex is defined as t by the enclosing environment: (let ((lex t)) (defvar f (lambda () (if lex "Lexical" "Dynamic")))) (I’ve changed the return values to strings to avoid confusion.) Calling (f) returns the value “Lexical”: > (f) "Lexical" Now we call f in an environment where lex has a different value, nil: (let ((lex nil)) (f)) The question is, w…

Unfortunately Version 2.7 had an issue that could occasionally cause programs to generate a “variable undefined” error, especially on platforms with a small amount of RAM.

This is now fixed in Version 2.7c, and I recommend you upgrade to this version:

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