Re: "Secret" operators

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From:

José Castro

Date:

February 2, 2005 02:22

Subject:

Re: "Secret" operators

Message ID:

20050202102242.GB8808@natura.di.uminho.pt

* McGlinchy, Alistair (Alistair.McGlinchy@marks-and-spencer.com) wrote:
> Hi All,
> 
> High in fun, but low in usefulness is -+- , a high precedence string
> numerifier. It sort of looks like an A C Clarke style spacestation so
> that's what I've been calling it. Although I'm not too sure that Larry's
> spaceship <=3D> would be able to dock to easily.

Of course it would!

  <=>
   |
   +
   |

Larry's probably been there a couple of times...

> Examples:
> 	print -+-'23a'    # prints 23
> 	print -+-'3.00'   # prints 3=09
> 	print -+-'1.2e3'  # prints 1200
> =09
> I know 0+ does the trick too, but binary + has a relatively low
> precedence. Perl will automatically numerify the arguments of the *
> operator but won't do so for x, !~ or =3D~. Hence this operator is =
> useful
> for removing unsightly parenthesises from some expressions.
> 
> 	print 0+'20GBP'   x 3;  # Wrong. Prints 20   =3D=3D
> 0+"20GBP20GBP20GBP"
> 	print (0+'20GBP') x 3;  # Wrong. x 3 is applied to the return of
> print
> 	print((0+'20GBP') x 3); # Right, but too Lispy=20
> 	print -+-'20GBP'  x 3;  # Right. Spacestation to the rescue!
> 
> Unfortunately -+- is bugged [*], but I'll leave these as gotcha's for
> your production code. :-)
> 
> 
> 
> Cheers,
> 
> Alistair
> 
> [*] You might want to consider: print    -+- '-2B'      x 5;  # Bug?
> 
> 
> -----------------------------------------------------------------------
> 
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
> =3D=3D
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--
Jose Alves de Castro <cog@cpan.org>
      http://jose-castro.org/

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