Hi Nathan,
Thank you for the explanation. Makes sense. I will pass this on in the
workshop.
Andreas
On 2017-06-19 14:12, Nathan Woodrow wrote:
> Hey Andreas,
>
> They are really two different things. $geometry is really a function that
> takes no arguments. This has been deprecated in favour calling with () e.g
> geometry(). @ is only for variables.
>
> So you can explain it that $ used to be a shorthand way of calling a function
> that took no arguments which has now been replaced with () at the end to call
> it. $area = area(). This becomes important because now we support optional
> arguments meaning you can take 0 to N arguments.
>
> - Nathan
>
> On Mon, Jun 19, 2017 at 9:53 PM, Neumann, Andreas <[email protected]> wrote:
>
>> Hi,
>>
>> While preparing for a workshop on expressions I wonder how to explain why
>> some variables are referenced with the $ sign (like $geometry) while other
>> variables start with the @ sign, like @row_number, @layer_name.
>>
>> I know that it has historical reasons and that variables with the @ sign are
>> newer and are implemented using a different technology.
>>
>> But are there plans to get rid of the old $ sign notation and move
>> everything to the @ sign notation?
>>
>> Just wonder how I best explain this to the participants of the workshop.
>>
>> Thanks for your reply,
>>
>> Andreas
>>
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