Syntax error (Re: multi-lang support in Ruby)

ruby-talk
1

Hi,

The following statement will generate a syntax error:

text.gsub!(/&#(\d+);/) do begin $1.to_i.chr rescue end; end

also, this is wrong:

text.gsub!(/&#(\d+);/) do $1.to_i.chr rescue end

but this is ok:

text.gsub!(/&#(\d+);/) do
begin
$1.to_i.chr
rescue
end;
end

Can anyone explain to me the general rules of when I can write code on
one line, and when I must write it on multiple lines?

Thanks!
Shannon

2

text.gsub!(/&#(\d+);/) do
begin
$1.to_i.chr
rescue
end;
end

Can anyone explain to me the general rules of when I can write code on
one line, and when I must write it on multiple lines?

I would trust that (\d+) will succesfully turn into an integer and forget
exception handling:

text.gsub!(!(/&#(\d+);/) { $1.to_i }

I don’t know what you could possibly have to rescue, anyway, because $1 will
always be a string in that context, so #to_i will succeed.

As a matter of style, I never use do … end on a single line. I use do …
end for “procedures” (i.e. do something) and { … } for evaluation purposes.

Sorry to not answer your question fully, but hopefully this will help a bit.

Gavin

···

From: “Shannon Fang” xrfang@hotmail.com [snipped]

3

Shannon Fang xrfang@hotmail.com writes:

Hi,

The following statement will generate a syntax error:

text.gsub!(/&#(\d+);/) do begin $1.to_i.chr rescue end; end

You just have to put more semicolons in at the end of statements:

text.gsub!(/&#(\d+);/) do begin $1.to_i.chr; rescue; end; end

Can anyone explain to me the general rules of when I can write code
on one line, and when I must write it on multiple lines?

Maybe “statements are terminated by an end of line or a semicolon.”

Ruby’s syntax is not “whitespace insensitive” like many other
languages, but it is generally intuitive – especially when not trying
to cram too much onto one line. :slight_smile: