* splat error

Ruby
1

Hello, i need some help here, when i run the following code i get the
error below. Why is that, according to the textbook it should work, also
looked it up in the cookbook, no luck there too. Thanks in advance.

def split_apart(first, *splat, last)
puts "first: #{first.inspect}, splat: #{splat.inspect}, " +
“last: #{last.inspect}”
end

split_apart(1,2)
split_apart(1, 2, 3)

Error:

/home/gribota1/NetBeansProjects/Analyzer/lib/rubymethods.rb:32: syntax
error, unexpected tIDENTIFIER, expecting tAMPER or ‘&’
def split_apart(first, *splat, last)
^

2

2010/5/4 Kerwin F. [email protected]:

split_apart(1, 2, 3)

Error:

/home/gribota1/NetBeansProjects/Analyzer/lib/rubymethods.rb:32: syntax
error, unexpected tIDENTIFIER, expecting tAMPER or ‘&’
def split_apart(first, *splat, last)
^

10:49:13 test_2$ allruby -ce ‘def s(a,*b,c) end’
CYGWIN_NT-5.1 padrklemme1 1.7.5(0.225/5/3) 2010-04-12 19:07 i686 Cygwin

ruby 1.8.7 (2008-08-11 patchlevel 72) [i386-cygwin]
-e:1: syntax error, unexpected tIDENTIFIER, expecting tAMPER or ‘&’
def s(a,*b,c) end
^

ruby 1.9.1p378 (2010-01-10 revision 26273) [i386-cygwin]
Syntax OK

jruby 1.4.0 (ruby 1.8.7 patchlevel 174) (2009-11-02 69fbfa3) (Java
HotSpot™ Client VM 1.6.0_20) [x86-java]
SyntaxError in -e:1: , unexpected tIDENTIFIER

def s(a,*b,c) end
^
11:16:32 test_2$

Cheers

robert

3

Ruby Knight wrote:

Hi Robert,

I tried putting end after the last brace but didn’t work. I am assuming
there is more to that ^ than just for illustrative purposes. Could you
explain to me why my code is not working? THanks!

In Ruby, formal parameters have a particular order:

def s(required, default=“default”, *variable_args, &block)

You cannot have a regular required parameter after an optional parameter
(denoted by *). The only thing you can have is a block parameter
(denoted by &) or nothing at all.

-Justin

4

def s(a,*b,c) end
^
11:16:32 test_2$

Cheers

robert

Hi Robert,

I tried putting end after the last brace but didn’t work. I am assuming
there is more to that ^ than just for illustrative purposes. Could you
explain to me why my code is not working? THanks!

5

On Tue, May 4, 2010 at 4:31 AM, Ruby Knight
[email protected]wrote:

Hi Robert,

I tried putting end after the last brace but didn’t work. I am assuming
there is more to that ^ than just for illustrative purposes. Could you
explain to me why my code is not working? THanks!

–
Posted via http://www.ruby-forum.com/.

Robert is saying that it works in 1.9.1 (see how it says Syntax OK), but
not
1.8.7 (where it pulls up the same error you had)

For 1.9, you can do something like this

def split_apart( first , *splat )
raise ArgumentError.new(‘wrong number of arguments (1 for 2)’) if
splat.size.zero?
last = splat.pop
puts “first: #{first.inspect}, splat: #{splat.inspect}, last:
#{last.inspect}”
end

Though I probably wouldn’t bother with the error myself, unless writing
code
for other people.

This is similar to how Rails’ find method works, it checks the last
argument
to see if it is a hash, then if it is, it pops it off (look at their
example
in the comments)

6

Ruby Knight wrote:

Hello, i need some help here, when i run the following code i get the
error below. Why is that, according to the textbook it should work, also
looked it up in the cookbook, no luck there too. Thanks in advance.

def split_apart(first, *splat, last)

What Robert is saying is that is valid syntax for ruby 1.9, but not for
ruby 1.8.

I don’t know what “the textbook” and “the cookbook” are that you refer
to, but they were probably written for 1.9.

ruby 1.9 is a substantially different language to ruby 1.8, which you
probably wouldn’t expect from the “minor” version bump.

7

On Tue, May 4, 2010 at 11:55 AM, Justin C. [email protected]
wrote:

It is legal in 1.9 and illegal in 1.8
HTH
R.

8

Hi –

On Tue, 4 May 2010, Robert D. wrote:

On Tue, May 4, 2010 at 11:55 AM, Justin C. [email protected] wrote:

It is legal in 1.9 and illegal in 1.8

Ditto in arrays as well as parameter lists. (Kind of interesting that
1.8.7 also gives the useless literal error.)

$ ruby -ve '[1,2,[3,4],5]’
ruby 1.8.7 (2008-05-31 patchlevel 0) [i686-darwin9.8.0]
-e:1: syntax error, unexpected ‘,’, expecting ‘]’
[1,2,[3,4],5]
^
-e:1: warning: useless use of a literal in void context

$ ruby191 -ve ‘p [1,2,*[3,4],5]’
ruby 1.9.1p376 (2009-12-07 revision 26041) [i386-darwin9.8.0]
[1, 2, 3, 4, 5]

David

–
David A. Black, Senior Developer, Cyrus Innovation Inc.

THE Ruby training with Black/Brown/McAnally
COMPLEAT Coming to Chicago area, June 18-19, 2010!
RUBYIST http://www.compleatrubyist.com

9

Thanks guys for all the input as well as the timely responses! I have to
upgrade my Ruby version then, i thought i had the latest version
installed but seems not.

Regards

10

Robert D. wrote:

On Tue, May 4, 2010 at 11:55 AM, Justin C. [email protected] wrote:

It is legal in 1.9 and illegal in 1.8
HTH
R.

Hmmm…noted.

-Justin

11

On Tue, May 4, 2010 at 5:35 AM, Ruby Knight
[email protected]wrote:

I’ve been pretty happy with rvm
http://rvm.beginrescueend.com/

12

FYI:

~/projects/jruby âž” jruby -e “def s(a,*b,c) end”
:1: -e:1: syntax error, unexpected tIDENTIFIER (SyntaxError)

def s(a,*b,c) end
^

~/projects/jruby âž” jruby --1.9 -e “def s(a,*b,c) end”

~/projects/jruby âž”

Gotta love an interpreter that’s two for the price of one :slight_smile:

On Tue, May 4, 2010 at 4:16 AM, Robert K.