HELP POPTOLISP Jon Cunningham, Oct 1984
This file provides a list of sample translations from Pop-11 to Poplog
Common Lisp. It is intended as quick reference reminder for Pop-11 users
learning Lisp (or Lisp users learning Pop-11), and should be used in
conjunction with a more detailed source. For information on how to run
Lisp, read HELP * CLISP. HELP * LISPVED explains how to prepare Lisp
programs using the VED editor. Details of the Lisp/Pop-11 mixed language
interface can be found in HELP * POPLISP.
CONTENTS - (Use <ENTER> g to access required sections)
1 Things to Avoid
2 Comments
3 Upper and Lower Case Letters
4 Quotes
5 Translation Summary
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1 Things to Avoid
-----------------------------------------------------------------------
The characters # . , @ and : all have special meanings in Common Lisp.
Don't use them unless you know what you're doing.
-----------------------------------------------------------------------
2 Comments
-----------------------------------------------------------------------
The Lisp end-of-line comment character is the same as Pop-11's, (the
semi-colon ";"), so you can comment programs in exactly the same way.
Bracketed comments are notated using #| and |#.
-----------------------------------------------------------------------
3 Upper and Lower Case Letters
-----------------------------------------------------------------------
Remember that lower case input is automatically translated to upper case
(except within a string). Thus
== 'hello
== 'HELLO
== 'Hello
== 'helLO
are all equivalent.
-----------------------------------------------------------------------
4 Quotes
-----------------------------------------------------------------------
The quote notation, has two forms: forward quote ', and back quote `.
Although the forward quote is the "standard" quote, which you will see
in text books, only the back-quote form allows the use of "comma"
notation. This is like "up-arrow" in Pop-11: examples are shown in the
section below. There are also other more subtle differences between
forward and back quote.
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5 Translation Summary
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Here are some examples of functionally similar Pop-11 and Lisp
expressions:
Pop-11 Lisp
---------------------- ---------------------
proc(arg1, arg2, arg3) --> (proc arg1 arg2 arg3)
proc() --> (proc)
[] --> nil
true --> t
a :: b --> (cons a b)
a <> b --> (append a b)
a = b --> (equalp a b)
a == b --> (eq a b)
a = [] --> (null a)
a + b --> (+ a b)
x -> y --> (setq y x)
'Hi there' --> "Hi there"
"oof" --> 'oof
[foo baz] --> '(foo baz)
[% foo, baz, grum %] --> (list foo baz grum)
[% "foo", baz %] --> (list 'foo baz)
[foo ^baz] --> `(foo ,baz)
[foo ^^baz grum] --> `(foo ,@baz grum)
hd(list) --> (car list)
tl(list) --> (cdr list)
hd(tl(tl(list))) --> (caddr list)
{foo baz} --> #(foo baz)
{% "foo", baz %} --> (vector 'foo baz)
{foo ^baz} --> `#(foo ,baz)
if c then s --> (if c s)
endif
if c then s --> (if c s s1)
else s1
endif
if c1 then s1 --> (cond
elseif c2 then s2 (c1 s1)
elseif c3 then s3 (c2 s2)
else s4 (c3 s3)
endif (t s4))
until c do s enduntil --> (loop until c do s)
while c do s endwhile --> (loop while c do s)
for item in list do --> (dolist (item list) s)
s
endfor
[% for item in list do --> (loop for item in list
s collect s)
endfor %]
for i from 0 to n do --> (dotimes (i n) s)
s
endfor
define greet(name); --> (defun greet (name)
[hello ^name] => (print `(hello ,name)))
enddefine;
--- C.all/lisp/help/poptolisp
--- Copyright University of Sussex 1987. All rights reserved.