(scm_unmemocar): Use !SCM_CONSP instead of SCM_IMP.
Minimize scope of local variable. Eliminate dependency on
macro DEBUG_EXTENSIONS.
(s_splicing): New error message string.
(scm_m_body): Issue 'bad body' message rather than 'missing
expression' message.
(scm_m_quote): Eliminate unnecessary copying.
(scm_m_lambda, scm_m_letstar, scm_m_letrec, scm_m_let): Leave the
checking of the body to scm_m_body.
(scm_m_do): Move comment to function header. Rename arg1 to
binding. Made the code a bit easier to read.
(evalcar): Removed.
(iqq): Added a comment. Changed the depth parameter to
unsigned. Use size_t for vector lengths. Make sure vector object
is gc protected as long as its contents are read. Add some syntax
checks. Get rid of unnecessary SCM_IMP test. Clean up the
control structure a bit.
(scm_m_delay): Added comment about the implementation of
scm_m_delay.
(scm_m_define): Add comment about guile's currying define
syntax. Renamed 'proc' to 'name'. Eliminate dependency on macro
DEBUG_EXTENSIONS. Simplified code a bit. Eliminate SICP code.
(scm_m_letrec1): Removed. Part of the functionality is taken
over by the new function 'transform_bindings'.
(transform_bindings): New function. Takes over some of the
functionality of removed function 'scm_m_letrec1', namely to split
a list of bindings into a reversed list of variables and a list of
initializers.
(scm_m_letrec): Call 'transform_bindings'.
(scm_m_let): Minimized scope of local variables. Renamed 'proc'
to 'temp' and 'arg1' to 'binding'. Eliminated redundant SCM_NIMP
test. Use 'transform_bindings'. Fixed scoping error with named
let (Thanks to Aubrey Jaffer for reporting the bug and to Neil
Jerram for suggesting the fix). Cleaned up the control structure
a bit.
(scm_m_expand_body): Use 'transform_bindings'. Eliminated
unnecessary consing. Eliminated unnecessary
SCM_DEFER/ALLOW_INTS.
(SCM_CEVAL): Un-obfuscated some loops.
