From: D T <tran55555@...>
Date: 2003-06-17T05:26:09+09:00
Subject: Tk methods return value

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Content-Type: text/plain; charset=us-ascii

Hi,
 
I am starting learning Ruby/Tk ( may-be later write a tutorial ).
I have a question about Ruby/Tk library implementation.
Why the methods like setting background, foreground, text, ... etc 
just return an empty string instead of 'self' ?
 
For example:
b = TkButton.new
b.text    # ==> without argument, this will return the text
            # this is same as b['text']  or b.cget('text').
 
# now
b.text( 'Hello World')  # ==> this returns a empty string, for me it is really useless.
 
If bg, fg, text ... etc like pack can return 'self' we could write code like:
 
b = TkButton.new.pack.bg('red').fg('black').text('Hello')
I know, we could write it like
b = TkButton.new('bg'=>'red', 'fg'=>'black', 'text'=>'Hello').pack
or
b = TkButton.new  { bg 'red'; fg 'black'; text 'Hello' }.pack # or put pack insdie { }
 
I just thought return empty string is really useless; so why not return 'self' then we could have other way to write the code ( and make it shorter )
# I know we could use 'configure' to combine
 
Is there any raison returns empty string ( or in same situation returns other things) ?
 

Thanks,
Dave
 


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--0-1454417893-1055795167=:33822
Content-Type: text/html; charset=us-ascii

<DIV>Hi,</DIV>
<DIV>&nbsp;</DIV>
<DIV>I am starting learning Ruby/Tk ( may-be later write a tutorial ).</DIV>
<DIV>I have a question about Ruby/Tk library implementation.</DIV>
<DIV>Why the methods like setting background, foreground, text, ... etc </DIV>
<DIV>just return an empty string instead of 'self' ?</DIV>
<DIV>&nbsp;</DIV>
<DIV>For example:</DIV>
<DIV>b = TkButton.new</DIV>
<DIV>b.text&nbsp;&nbsp;&nbsp; # ==&gt; without argument, this&nbsp;will return the text</DIV>
<DIV>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; # this is same as b['text']&nbsp; or b.cget('text').</DIV>
<DIV>&nbsp;</DIV>
<DIV># now</DIV>
<DIV>b.text( 'Hello World')&nbsp; # ==&gt; this returns a empty string, for me it is really useless.</DIV>
<DIV>&nbsp;</DIV>
<DIV>If bg, fg, text ... etc like pack can return 'self' we could write code like:</DIV>
<DIV>&nbsp;</DIV>
<DIV>b = TkButton.new.pack.bg('red').fg('black').text('Hello')</DIV>
<DIV>I know, we could write it like</DIV>
<DIV>b = TkButton.new('bg'=&gt;'red', 'fg'=&gt;'black', 'text'=&gt;'Hello').pack</DIV>
<DIV>or</DIV>
<DIV>
<DIV>b = TkButton.new&nbsp; {&nbsp;bg 'red'; fg 'black'; text 'Hello' }.pack # or put pack insdie { }</DIV>
<DIV>&nbsp;</DIV>
<DIV>I just thought return empty string is really useless; so why not return 'self' then we could have other way to write the code ( and make it shorter )</DIV>
<DIV># I know we could use 'configure' to combine</DIV>
<DIV>&nbsp;</DIV>
<DIV>Is there any raison returns empty string (&nbsp;or in same situation returns other things) ?</DIV>
<DIV>&nbsp;</DIV></DIV>
<DIV>Thanks,</DIV>
<DIV>Dave</DIV>
<DIV>&nbsp;</DIV><p><hr SIZE=1>
Do you Yahoo!?<br>
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