|
SEQ | (SEQ ,@forms) | S |
|
| evaluates forms sequentially and returns values of evaluating last
form (cf. Scheme's BEGIN) | |
|
| (SEQ) | S |
|
| returns false | |
|
{ ... } | { ,@body } | S |
|
| SEQ abbreviation == (SEQ ,@body). | |
|
IF | (IF ,test ,then [ ,else ]) | S |
|
| evaluates either ,then if ,test is non-false
otherwise evaluates ,else (cf. Scheme's IF). The
,else expression defaults to false. | |
|
AND | (AND ,form ,@forms) | S |
|
| == (IF ,form (AND ,@FORMS)) | |
|
| (AND ,form) | S |
|
| == ,form | |
|
OR | (OR ,form ,@forms) | S |
|
| == (SEQ (DEF x ,form) (IF x x (OR ,@FORMS))) | |
|
| (OR ,form) | S |
|
| == ,form | |
|
UNLESS | (UNLESS ,test ,@body) | S |
|
| == (IF (NOT ,test) (SEQ ,@body)) | |
|
WHEN | (WHEN ,test ,@body) | S |
|
| == (IF ,test (SEQ ,@body)) | |
|
COND | (COND (,test ,@body) ...) | S |
|
| evaluates (SEQ ,@body) of first clause
whose ,test evaluates to
non-false (cf. Dylan's CASE and Scheme's COND). | |
|
CASE[-BY] | (CASE[-BY] ,value [ ,test ]((,@keys) ,@body) ...) | S |
|
| evaluates ,value and then evaluates (SEQ ,@body)
of first clause for which (,test ,value ,key) returns non-false
(cf. Dylan's SELECT and Scheme's CASE). N.B., each
key is evaluated, thus symbols must be quoted. The default
,test for the CASE form is ==. | |
|
OPF | (OPF ,place ,expr) | S |
|
| == (SEQ (DEF _ ,place) (SET ,place ,expr)), where
,place is evaluated only once. For example,
(OPF x (+ _ 1)) == (SET x (+ x 1)). | |
|
SWAPF | (SWAPF ,x ,y) | S |
|
| == (SEQ (DEF tmp ,x) (SET ,x ,y) (SET ,y tmp)),
where ,x and ,y are evaluated only once. | |
|
ROTF | (ROTF ,x ,y ,@places) | S |
|
| == (SET (TUP ,x ,y ,@places) (TUP ,y ,@places ,x))
where ,x, ,y, and ,@places) are evaluated only
once and (SET (TUP ...) val) stands for parallel assignment. | |
|
call | (,f ,@args) | S |
|
| evaluates ,f and then ,@args in left to right
order and then calls ,f with the evaluated arguments. | |
|
REP | (REP ,name ((,var ,init) ...) ,@body) | S |
|
| defines a recursive loop (cf., Dylan's ITERATE or Scheme's (LET ,var ...)). | |
|
ESC | (ESC ,name ,@body) | S |
|
| evaluates (SEQ ,@body) with an exit
function of a single parameter, x, bound to
,name that if called, will cause ESC to
return the value of x
(cf. Dylan's BLOCK/RETURN). It is illegal
to call the exit function
after the execution of the creating ESC form (i.e., no upward
continuations). | |
|
FIN | (FIN ,protected ,@cleanups) | S |
|
| ensures that (SEQ ,@cleanups) is evaluated whether
or not an ESC upwards exit is taken
during the dynamic-extent of ,protected
(cf. Dylan's BLOCK/CLEANUP form and CL's
UNWIND-PROTECT). The result of a FIN form is the
result of evaluating its protected form. | |
|
ASSERT | (ASSERT ,test ,message ,@args) | S |
|
| == (UNLESS ,test (ERROR ,message ,@args)) | |
|
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