Learning Lisp/Scheme - Re: John McCarthy

On 27 October 2011 00:41, Toby Thain <toby at telegraphics.com.au> wrote: I don't currently have the spare budget for buying books, but I do have a few PDFs: * Common Lisp - A gentle introduction to symbolic computation book * COMMON LISP: An Interactive Approach ... and some elderly text. As I try to read them, I get this sinking feeling after half a dozen pages where what started off making sense quietly and subtly turns to word soup. Arithmetic tends to get replaced with gibberish that resembles English but isn't, along the lines of "ah, but if we use a quote, then the we don't get the name of the atom, we get the value." And it quickly starts feeling like /Alice through the Looking Glass:/ ? Alice was walking beside the White Knight in Looking Glass Land. "You are sad." the Knight said in an anxious tone: "let me sing you a song to comfort you." "Is it very long?" Alice asked, for she had heard a good deal of poetry that day. "It's long." said the Knight, "but it's very, very beautiful. Everybody that hears me sing it - either it brings tears to their eyes, or else -" "Or else what?" said Alice, for the Knight had made a sudden pause. "Or else it doesn't, you know. The name of the song is called 'Haddocks' Eyes.'" "Oh, that's the name of the song, is it?" Alice said, trying to feel interested. "No, you don't understand," the Knight said, looking a little vexed. "That's what the name is called. The name really is 'The Aged, Aged Man.'" "Then I ought to have said 'That's what the song is called'?" Alice corrected herself. "No you oughtn't: that's another thing. The song is called 'Ways and Means' but that's only what it's called, you know!" "Well, what is the song then?" said Alice, who was by this time completely bewildered. "I was coming to that," the Knight said. "The song really is 'A-sitting On a Gate': and the tune's my own invention." ? (from http://homepages.tcp.co.uk/~nicholson/alice.html) So, now, see, this is a list, but it's also an expression, but if we call it as a function then the expression modifies the atoms in the lisp, but it's still an expression, because all lists are expressions but only some expressions are functions. Some lists are cons but cons can be a list of things, but be careful not to muddle up atoms and conss. You see? Perfectly simple! I find this tends to happen before the page count is in double digits. So tonight, I tried working through some of this with Stephane Tsacas on chat. I tried installing Steel Bank Common Lisp, but every other thing I type generates 10 lines of error messages and takes me into a debugger. Stephane has recommended Allegro Common Lisp, but it doesn't even seem to understand cursor up/cursor down. And don't talk to me about Emacs. I tried and failed to follow the tutorial in 1988 and I'm a lot grumpier and less flexible nowadays than I was then. We shall see. I shall have another try. If I bounce off again, a friend has offered me some Python tuition. Perhaps C21 languages might be less prone to making my aging brain do the 'splodey thing. ;?) -- Liam Proven ? Info & profile: http://www.google.com/profiles/lproven Email: lproven at cix.co.uk ? GMail/GoogleTalk/Orkut: lproven at gmail.com Tel: +44 20-8685-0498 ? Cell: +44 7939-087884 ? Fax: + 44 870-9151419 AIM/Yahoo/Skype: liamproven ? MSN: lproven at hotmail.com ? ICQ: 73187508