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I'm thinking about adding and using a macro in the to simplify the Scheme reference implementation. Any comments? Currently, the sample implementation includes many lines that look like this: ; Run (n-expr-first port) and put results in various variables (let* ((basic-full-results (n-expr-first port)) (basic-special (car basic-full-results)) (basic-value (cadr basic-full-results))) ...) I'm thinking about using an R5RS-style macro so all such lines would instead look like: (let-splitter (basic-full-results basic-special basic-value) (n-expr-first port) ...) The macro definition would look like this: ; I'm intentionally requiring exactly 3 variables for now, since ; that's all that's used. It could be modified later to be more flexible. (define-syntax let-splitter (syntax-rules () ((let-splitter (full first-value second-value) expr body ...) (let* ((full expr) (first-value (car full)) (second-value (cadr full))) body ... )))) Guile 1.8 doesn't enable R5RS macros by default, but they can be enabled with: (use-syntax (ice-9 syncase)) It appears that the same is true for guile 1.6: http://www.gnu.org/software/guile/docs/docs-1.6/guile-ref/Syntax-Rules.html#Syntax%20Rules I believe most other Schemes in wide use have R5RS macros. Even old/partial Schemes that did NOT support R5RS macros should be easily adaptable (it doesn't particularly require a hygenic macro system). I'd probably do the same with the Common Lisp implementation (that's outside this group's scope, but I thought I'd mention it). Comments? Good idea? Bad idea? --- David A. Wheeler