Scheme Implementation Choices

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MIT Scheme Scheme 48 RScheme MzScheme Guile Bigloo Chicken Gambit Gauche Scm
version 7.7.90.+ 1.3 0.7.3.4-b3u 360 1.8.1 2.8c 2.5 4.0 beta 20 0.8.8 5e3
null-combination true false false true false false true false true true
r5rs-letrec false true false false true true false true false false
case-sensitive false false true false false true false false false false
non-ascii-integer-to-char false true false false false false false false false false
no-syntax-rules false false true false false false false true false false
undefined-settable false false true false false false true false false false
liberal-force false false true false false false true true true false
promises-are-thunks false true false false false true false false false false
implicit-forcing false false false false false false false false false false
recursive-forcing correct correct naive correct correct correct correct correct correct correct
self-evaluating-vectors true false false true true false false false true true
exact-sqrt true false false true false false false true false false
exact-times-zero false false false true true false false true false false
exact-div-zero true false false true false false false true false false
allows-div-by-inexact-zero false false true true true true false true true true
allows-inexact-div-by-zero false false true false false true false false true true
allows-div-by-exact-zero false false false false false false false false true true
literal-bignums true true true true true integer_overflow coerce_to_floats true true true
computed-bignums true true true true true integer_overflow coerce_to_floats true true true
literal-rationals true true true true true false true true true true
literal-complexes true true true true true false false true true true
exact-rationals true true true true true false false true true false
exact-complexes true true true true false false false true false false
nonreal-inexact-zero-i false false false false false false false true false false
inexact-denominator standard standard exact_one standard standard false false standard inexact_one standard
no-nary-minus false true false false false false false false false false
unstable-string-to-number true false true false true false false false false false
strict-remainder false false false false true true false false false true
no-angle false false true false false true false false false false
no-imag-part false false false false false true false false false false
no-magnitude false false true false false true false false false false
no-make-polar false false false false false true true false false false
no-make-rectangular false false false false false true true false false false
no-real-part false false false false false true false false false false
no-transcript-on false true true false true false true false true false
no-transcript-off false true true false true false true false true false
no-port? false true true false false false false false false true
no-scheme-report-environment true false true false false false false false false false
no-null-environment true false true false false false false false false false
no-interaction-environment true false true false false false false false false false
no-rationalize false false true false false true true false true true
no-numerator false false false false false true true false false false
no-denominator false false false false false true true false false false