From: Robert Klemme <shortcutter@...>
Date: 2009-03-10T17:18:29+09:00
Subject: Re: Setting the contents of a file to a variable?

2009/3/9 Torli Birnbauer <aipir@sympatico.ca>:
> Robert Klemme wrote:
>> tmp$ cat >| x <<EOF
>
> All programming languages can be abused. This does not make the abuser a
> hero!

That was just a tool to create the file.  I could have also used a
text editor, echo commands or whatever.

> PS: whose main message is in the "ps" addendum  must have missed the
> point totally!

I am sorry, but I believe you are missing the point.  The main message
was in this line

17:45:25 tmp$ allruby -e 'p File.read("x"), File.readlines("x")'

In other words: with methods like File.read and File.readlines which
can be as simply used as demonstrated above there is simply no point
in using *any* of the presented block forms - especially not
File.open("zorba.data", &:readlines) which does not work in pre 1.9
versions - for reading a complete file into a single variable (either
as String or as Array).  These methods are as safe with regard to file
handle closing as the block form of File.open (which I usually
advocate when appropriate). *That* is the point that badboy tried to
make.

Having said that, the simplest and most efficient form to read a
number from a file that does not contain much more are probably these
- depending on whether a float or an integer is to be read:

num = File.read("file1.txt").to_i
num = File.read("file1.txt").to_f

If file contents are not guaranteed and input verification needs to be
done then you can do this as a first line of defense

num = Integer(File.read("file1.txt"))
num = Float(File.read("file1.txt"))

Of course, arbitrary more complex parsing schemes can be devised.

Cheers

robert


-- 
remember.guy do |as, often| as.you_can - without end