Fxri

ruby-talk
1

Hi,

I'm using fxri and I have required a ruby file as follows:

require "c:\myWork\motor.rb"

My question is, how do I reload this file when I make changes?

Thanks.

2

Hi,

I'm using fxri and I have required a ruby file as follows:

require "c:\myWork\motor.rb"

1. You don't generally want to use Windows-style paths at all.
2. You don't generally want to use absolute paths at all.
3. You don't generally want to use the .rb extension with #require.

My question is, how do I reload this file when I make changes?

3. You want to #load the file, not #require the file. You MUST use the
.rb extension with #load.

-austin

···

On 3/2/07, zeeman11@gmail.com <zeeman11@gmail.com> wrote:
--
Austin Ziegler * halostatue@gmail.com * http://www.halostatue.ca/
               * austin@halostatue.ca * You are in a maze of twisty little passages, all alike. // halo • statue
               * austin@zieglers.ca

3

Alle venerdì 2 marzo 2007, zeeman11@gmail.com ha scritto:

Hi,

I'm using fxri and I have required a ruby file as follows:

require "c:\myWork\motor.rb"

My question is, how do I reload this file when I make changes?

Thanks.

I assume you're speaking about the irb session embedded in fxri. If I'm wrong,
my answer won't be very useful.

I think the cleanest way to reload a file is to use the load method:

load 'c:\myWork\motor.rb'

(note that with load you need to specify the extension).
Different from require, load doesn't check whether the file already is in $"
(the list of required files), although this is not explicitly said in the ri
documentation, and can't load C extensions.

Another way to reload the file should be to remove it from $" and use require.

In both cases, you must be careful. Suppose the file a.rb contains the
following:

---File a.rb---

class C
def method1
  "method1"
end

def method2
  "method2"
end
end

In the interactive session, you do:

require 'a' #you could also do load 'a.rb'
c=C.new
c.method1
=> "method1"

c.method2
=> "method2"

Then you modify a.rb:

---File a.rb modified---
class C

def method2
  "method2"
end

end #you removed the definition of method1

You go back to the interactive session and type

c.method2
=> "method2"

c.method1 #you'd expect a NoMethodError, since the method has been removed.
=> "method1"

c1=C.new #create a new instance of C using the last definition

c1.method1
=>NoMethodError

The point is that loading the file again doesn't clear whatever it was defined
in it the first time it was loaded. I think (but I'm only guessing) that
loading for a second time a file which contains a class or a module looks a
bit like (but it's different from) reopening the class or module. For
instance, if in the modified a.rb you'd added the line

undef_method :method1

inside the definition of C, then calling c.method1 would have raised a
NoMethodError.

I hope all this helps

Stefano

4

Great, thanks.