Language documentation ( was Re: Computing Industry shams)

[vermicule]

A|B, where A and B can be arbitrary REs, creates a regular expression
that will match either A or B. An arbitrary number of REs can be
separated by the "|" in this way. This can be used inside groups (see
below) as well. As the target string is scanned, REs separated by "|"
are tried from left to right. When one pattern completely matches, that
branch is accepted. This means that once A matches, B will not be
tested further, even if it would produce a longer overall match. In
other words, the "|" operator is never greedy. To match a literal "|",
use \|, or enclose it inside a character class, as in [|].

--end quote--

Note: In other words, the "|" operator is never greedy.

Note the need to inject the high-brow jargon "greedy"here as a
latch on sentence.

What is so hard to understand ?
Should be perfectly clear even to a first year undergraduate.

As for "greedy" even a minimal exposure to Djikstra's shortest path
algorithm would have made the concept intuitive. And from memory,
that is the sort of thing done in Computing 101 and in Data Structures and
Algorithms 101

It seems to me that you want the Python doc to be written for morons.
And that is not a valid complaint.

 

[=?iso-8859-1?q?M=E5ns_Rullg=E5rd?=]

[...]


It seems to me that you want the Python doc to be written for morons.

Not for morons, but for trolls. Don't feed them.

 

[alex goldman]

What is so hard to understand ?
Should be perfectly clear even to a first year undergraduate.

As for "greedy" even a minimal exposure to Djikstra's shortest path
algorithm would have made the concept intuitive. And from memory,
that is the sort of thing done in Computing 101 and in Data Structures
and Algorithms 101

It seems to me that you want the Python doc to be written for morons.
And that is not a valid complaint.

He's right actually. If we understand the term "greedy" as it's used in
graph search and optimization algorithms, Python's RE matching actually IS
greedy.

 

[=?iso-8859-1?q?M=E5ns_Rullg=E5rd?=]

He's right actually. If we understand the term "greedy" as it's used in
graph search and optimization algorithms, Python's RE matching actually IS
greedy.

If we, more reasonably, use the meaning of "greedy" that is commonly
used when talking about regular expressions, there is nothing wrong
with the Python docs, and Xah Lee remains the troll he has always
been.

 

[James Stroud]

http://www.developer.com/lang/article.php/10924_3330231_3

He's right actually. If we understand the term "greedy" as it's used in
graph search and optimization algorithms, Python's RE matching actually IS
greedy.

--
James Stroud
UCLA-DOE Institute for Genomics and Proteomics
Box 951570
Los Angeles, CA 90095

http://www.jamesstroud.com/

 

[Sean Burke]

He's right actually. If we understand the term "greedy" as it's used in
graph search and optimization algorithms, Python's RE matching actually IS
greedy.

No, you're just confused about the optimization metric.
In regexes, "greedy" match optimizes for the longest match,
not the fastest.

And this is common regex terminology - man perlre and you will
find discussion of "greedy" vs. "stingy" matching.

-SEan

 

[alex goldman]

No, you're just confused about the optimization metric.
In regexes, "greedy" match optimizes for the longest match,
not the fastest.

And this is common regex terminology - man perlre and you will
find discussion of "greedy" vs. "stingy" matching.

Read what you quoted again. Everyone (Xah, vermicule, myself) was talking
about "greedy" as it's used in graph search and optimization algorithms.

 

[alex goldman]

However the original quote was in the context of regular expressions, so
discussion of the terminology used in regular expressions is far more
relevant than the terminology used in graph search and optimisation
algorithms.

I replied to "And from memory, that is the sort of thing done in Computing
101 and in Data Structures and Algorithms 101", and I fully explained what
I meant by "greedy" as well. There was no ambiguity.

 

[Lawrence Kirby]

Sean Burke wrote:
....


Read what you quoted again. Everyone (Xah, vermicule, myself) was talking
about "greedy" as it's used in graph search and optimization algorithms.

However the original quote was in the context of regular expressions, so
discussion of the terminology used in regular expressions is far more
relevant than the terminology used in graph search and optimisation
algorithms.

Lawrence

 

[Lawrence Kirby]

Lawrence Kirby wrote:
....


I replied to "And from memory, that is the sort of thing done in Computing
101 and in Data Structures and Algorithms 101", and I fully explained what
I meant by "greedy" as well. There was no ambiguity.

My response talks about relevance, not ambiguity.

Lawrence

 

[alex goldman]

My response talks about relevance, not ambiguity.

Well, your response was irrelevant.

 

[Keith Thompson]

Lawrence Kirby wrote: [snip]

My response talks about relevance, not ambiguity.

Well, your response was irrelevant.

This entire discussion is irrelevant to most, if not all, of the
newsgroups to which it's being posted. comp.lang.c, where I'm reading
this, is for discussion of the C programming language; I see nothing
about C.