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TorgoX (1933)


"Il est beau comme la retractilité des serres des oiseaux rapaces [...] et surtout, comme la rencontre fortuite sur une table de dissection d'une machine à coudre et d'un parapluie !" -- Lautréamont

Journal of TorgoX (1933)

Friday September 19, 2003
10:32 PM

Parsing Zen

[ #14798 ]
Dear Log,

«Example 0.10:
Let us consider some simple examples of languages over an alphabet . The empty-set Ø is a language. The set {e} which contains only the empty string is a language. Notice that Ø and {e} are two distinct languages.»

--from Aho & Ullman's The Theory of Parsing, Translation, and Computing (1972)
volume 1: "Parsing"
chapter 0 [ugh]: "Mathematical Preliminaries"
page 16

Yes. Let us all turn our attention to the crucial difference between a language where you can't say anything, versus a language where you can say only nothing.


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  • use Storable qw( freeze );

    $a = undef;
    $b = [];

    ( freeze($a) ne freeze($b) ) and
        print "Naturally :-)\n";

    I'm sure it's not too hard to argue the merit and usefulness of empty and undefined sets when viewed in the context of code development.

  • Lao Tzu and Chuang Tzu were discussing the virtues of the men of old.

    Lao Tzu began, "The men of old had a language of pure Tao, in which the only word was silence."

    Chuang Tzu responded, "But how did they express the absence of silence?"

    At this, Lao Tzu was enlightened.

    Chuang Tzu continued, "If you want TCL 7.X, you know where to get it."

    At this, Lao Tzu realized that Chuang Tzu needed to get out more.
  • Pai-chang wished to send a monk to open a new monastery. He told his pupils that whoever answered a question most ably would be appointed. Placing a water jug on the ground, he asked, "Who can say what this is without calling its name?" The head Monk said, "No one can call it a wooden sandal." Kuei-shan, the cooking monk, tipped over the jug with his foot and went out. Pai-chang laughed and said: "The head monk loses." And Kuei-shan became the head Master of the new monastery.