newlispfanclub.alh.net

The (directory) function gives back all files in a directory.

I would like a function like this:

(files "C:\temp\A*.txt")

which would return all matching text-files in that dir.

try a function defined using directory and regex say:

(define (files d f) (filter (lambda (x) (regex f x)) (directory d)))

usage would be lke (files "c:/temp/" "[Aa][a-z]+\.txt")
that is first is the directory as a string the second is a regular expression as a string (not quite as friendly as filename wildcards but more powerful).
Filter works because will return nil if there is no match.

Regards
Nigel

Thanks Nigel,

Nice and short. Have not thought enough about it. :-)
Have to test it with big files-counts.

On windows as long as you don't go via newlisp-tk but directly with newlisp.exe you also can do:

(exec "dir /b c:/*.txt")

Note, that the forward slash is Ok, /b will make sure that you only get filename info and exec will put all the filename strings nicely in a list just like 'directory'.

On Linux and other UNIXs this will work in both, newlisp-tk and streight newlisp:

(exec "ls /*.txt")

In any case I suspect that Nigels' suggestion will be the faster method and with less computing resorces, as it doesn't need to start a new shell process. Since 7.3.8 you also can write:

(filter (fn (x) (regex f x)) (directory d))

which makes it a tiny bit more readable and shorter (fn instead of lambda).

Lutz

So this is the way to go:

(define (files fpath fpattern caseflag)(filter(fn (x)(regex fpattern x caseflag))(directory fpath)))

(files "c:/temp/" "^A.*\.mbi" 0)

When started from the tk-console the text-output speed of the console is the limiting factor when output sveral thousand file-names.
A more matching search-pattern return very fast the wanted files.

But why does enabling case-insensitiveness does not work:
Changing the order of the calls changes the results.
Why do it not give the correct result every time?

It seems to be a bug in regex.

Only when something in the search pattern is changed, it get a new result set. Only changing the case of a letter does not get it. When you change to another letter, the sensitive flag is processed correctly.

The compiled regular expression pattern is cached internally and only recompiled, when changed for speed optimizations.

I have fixed this, so in the next version an options flag change will also trigger a pattern recompile.

Yes, the tk output console slows down the more it gets filled up, you may want to try out stuff sometimes by using newlisp.exe in a raw mode, if you have to watch huge output capacities; but I guess that TK is an integral part of your application?

Lutz