Arithmetic

[Jason van Zyl <jv...@periapt.com>]

Hey,

Can we add arithmetic to the template specification.
Arithmetic is parsing fine, so I'd like to add
the functionality to the visitor. Actually I
would have to add the functionality to the
visitor anyway to deal with arithmetic that
happened in conditional expressions like:

#if (($a + $b) > $c)

And I propose to use the #set like this:

#set $foo = 1
#set $foo = $foo + 1
#set $foo = ($a - $b) + $c

jvz.

-- 

Jason van Zyl
jvanzyl@periapt.com

Re: Arithmetic

[Jason van Zyl <jv...@periapt.com>]

On Thu, 14 Sep 2000, Daniel L. Rall wrote:

> Jason van Zyl wrote:
> > 
> > Hey,
> > 
> > Can we add arithmetic to the template specification.
> > Arithmetic is parsing fine, so I'd like to add
> > the functionality to the visitor. Actually I
> > would have to add the functionality to the
> > visitor anyway to deal with arithmetic that
> > happened in conditional expressions like:
> > 
> > #if (($a + $b) > $c)
> > 
> > And I propose to use the #set like this:
> > 
> > #set $foo = 1
> > #set $foo = $foo + 1
> > #set $foo = ($a - $b) + $c
> 
> Yay, +1!
> (sorry for the delayed response)

Not a problem, have my head down in an overhaul
anyway :)

jvz.
 

-- 

Jason van Zyl
jvanzyl@periapt.com

Re: Arithmetic

["Daniel L. Rall" <dl...@collab.net>]

Jason van Zyl wrote:
> 
> Hey,
> 
> Can we add arithmetic to the template specification.
> Arithmetic is parsing fine, so I'd like to add
> the functionality to the visitor. Actually I
> would have to add the functionality to the
> visitor anyway to deal with arithmetic that
> happened in conditional expressions like:
> 
> #if (($a + $b) > $c)
> 
> And I propose to use the #set like this:
> 
> #set $foo = 1
> #set $foo = $foo + 1
> #set $foo = ($a - $b) + $c

Yay, +1!
(sorry for the delayed response)
-- 

Daniel Rall <dl...@collab.net>
http://collab.net/ | open source | do the right thing

Re: Arithmetic

[Frank Conradie <fr...@opticode.co.za>]

----- Original Message -----
From: "Daniel L. Rall" <dl...@collab.net>
To: <ve...@jakarta.apache.org>
Sent: Friday, September 15, 2000 3:39 AM
Subject: Re: Arithmetic


> bob wrote:
> > [snip]
> > > As unbelievable as it may seem, I've found that even graphic designers
> > > are capable of simple arithmatic.  ;)
> >
> > Oh sure, I'm not disputing that at all.
> >
> > My point is that if you choose WebMacro/Velocity for it's
> > benefits of MVC separation, and then add back arithmetic, you
> > possibly have taken a step back from the whole point of the MVC
> > stuff.  Arithmetic tends to lead to logic, and we don't want
> > to encourage logic in the templates, necessarily.
>
> My first hand experience--from having to write and use helper object for
> WebMacro--leads me to believe that the arithmetic used in templates
> doesn't constitute business logic.  It is generally presentation
> related.  I understand your concern about MVC separation (I'm all about
> that), and was not trying to make light of it (just of the arithmetic
> part ;).  I just have a different opinion about how and why template
> designers use arithematic.  =)

I have to agree with Daniel here - I had a look through a lot of our
templates, and the need for arithmetic almost always has something to do
with presentational logic.

Frank

Re: Arithmetic

["Daniel L. Rall" <dl...@collab.net>]

bob wrote:
> [snip]
> > As unbelievable as it may seem, I've found that even graphic designers
> > are capable of simple arithmatic.  ;)
> 
> Oh sure, I'm not disputing that at all.
> 
> My point is that if you choose WebMacro/Velocity for it's
> benefits of MVC separation, and then add back arithmetic, you
> possibly have taken a step back from the whole point of the MVC
> stuff.  Arithmetic tends to lead to logic, and we don't want
> to encourage logic in the templates, necessarily.

My first hand experience--from having to write and use helper object for
WebMacro--leads me to believe that the arithmetic used in templates
doesn't constitute business logic.  It is generally presentation
related.  I understand your concern about MVC separation (I'm all about
that), and was not trying to make light of it (just of the arithmetic
part ;).  I just have a different opinion about how and why template
designers use arithematic.  =)
-- 

Daniel Rall <dl...@collab.net>
http://collab.net/ | open source | do the right thing

Re: Arithmetic

[bob <bo...@accurev.com>]

> > Jason says that folks have requested this.
> > 
> > I'm fundamentally opposed (but won't veto it).
> > 
> > But, I'd like to collect use-cases from folks, as to
> > why they think they need arithmetic in a template.
> > 
> > I think we can find Better Solutions than putting
> > math in HTML by a graphic-designer.
> 
> As unbelievable as it may seem, I've found that even graphic designers
> are capable of simple arithmatic.  ;)

Oh sure, I'm not disputing that at all.  

My point is that if you choose WebMacro/Velocity for it's
benefits of MVC separation, and then add back arithmetic, you
possibly have taken a step back from the whole point of the MVC
stuff.  Arithmetic tends to lead to logic, and we don't want
to encourage logic in the templates, necessarily.

	-bob

Re: Arithmetic

["Daniel L. Rall" <dl...@collab.net>]

bob wrote:
> 
> Jason says that folks have requested this.
> 
> I'm fundamentally opposed (but won't veto it).
> 
> But, I'd like to collect use-cases from folks, as to
> why they think they need arithmetic in a template.
> 
> I think we can find Better Solutions than putting
> math in HTML by a graphic-designer.

As unbelievable as it may seem, I've found that even graphic designers
are capable of simple arithmatic.  ;)
-- 

Daniel Rall <dl...@collab.net>
http://collab.net/ | open source | do the right thing

Re: Arithmetic

[Travis Low <tl...@iitedge.com>]

Oh, then my apologies.  I misunderstood.

As for the Better Solution, it should syntactically resemble other
Good Solutions.  I believe the exact syntax doesn't matter.  It's more
important to not require designers to use a syntax that they don't
already use.  So if designers are accustomed to the ersatz-method
invocation syntax, then that would be fine.  Otherwise, I'd go with
the #set syntax that Jason proposed on the velocity-users list.

As for being "heavily promoted", I wouldn't do that.  I'd just
document it with the rest of the core velocity template language.  I
do believe that arithmetic operations should be in the core, since
arithmetic is a core function of graphic design, especially of web
design.

Travis

Jason van Zyl wrote:
> 
> On Mon, 11 Sep 2000, Travis Low wrote:
> 
> > As a graphic artist (turned developer) with 5 years of production art
> > experience, and 20 years freelance experience, I'd rather you
> > explained why I DON'T need arithmetic.  Or show me a graphics shop
> > where there are no rulers or calculators.  Or show me a popular
> > graphics program that doesn't have little rulers around the display
> > area.  :-)
> >
> > Artists have used simple arithmetic since art was invented.
> >
> > I did post some use cases to the velocity-users list, btw.
> 
> Bob wasn't implying that graphic designers don't use
> arithmetic. I think he was saying that if there is
> a need, there might be a better way to have it present
> in templates.
> 
> Maybe through a series of helper methods:
> 
> $tool.add(...)
> $tool.substract(...)
> 
> I'm not exactly sure what all the helper methods would
> look like, but we might even be able to have helper
> methods for logical and relational operations.
> 
> I myself would like to have arithmetic be possible,
> but it might not necessarily be something
> that's heavily promoted. Arithmetic may be
> allowed, but we could also provide a set of
> helper methods that can be used for arithmetic
> for possibly easier to understand templates.
> 
> jvz.
> 
> > bob wrote:
> > >
> > > Jason says that folks have requested this.
> > >
> > > I'm fundamentally opposed (but won't veto it).
> > >
> > > But, I'd like to collect use-cases from folks, as to
> > > why they think they need arithmetic in a template.
> > >
> > > I think we can find Better Solutions than putting
> > > math in HTML by a graphic-designer.
> > >
> > >         -bob
> > >
> > > On Sat, 9 Sep 2000, Jason van Zyl wrote:
> > >
> > > > Hey,
> > > >
> > > > Can we add arithmetic to the template specification.
> > > > Arithmetic is parsing fine, so I'd like to add
> > > > the functionality to the visitor. Actually I
> > > > would have to add the functionality to the
> > > > visitor anyway to deal with arithmetic that
> > > > happened in conditional expressions like:
> > > >
> > > > #if (($a + $b) > $c)
> > > >
> > > > And I propose to use the #set like this:
> > > >
> > > > #set $foo = 1
> > > > #set $foo = $foo + 1
> > > > #set $foo = ($a - $b) + $c
> > > >
> > > > jvz.
> > > >
> > > > --
> > > >
> > > > Jason van Zyl
> > > > jvanzyl@periapt.com
> > > >

Re: Arithmetic

[Jason van Zyl <jv...@periapt.com>]

On Mon, 11 Sep 2000, Travis Low wrote:

> As a graphic artist (turned developer) with 5 years of production art
> experience, and 20 years freelance experience, I'd rather you
> explained why I DON'T need arithmetic.  Or show me a graphics shop
> where there are no rulers or calculators.  Or show me a popular
> graphics program that doesn't have little rulers around the display
> area.  :-)
> 
> Artists have used simple arithmetic since art was invented.
> 
> I did post some use cases to the velocity-users list, btw.

Bob wasn't implying that graphic designers don't use
arithmetic. I think he was saying that if there is
a need, there might be a better way to have it present
in templates.

Maybe through a series of helper methods:

$tool.add(...)
$tool.substract(...)

I'm not exactly sure what all the helper methods would
look like, but we might even be able to have helper
methods for logical and relational operations.

I myself would like to have arithmetic be possible,
but it might not necessarily be something
that's heavily promoted. Arithmetic may be
allowed, but we could also provide a set of
helper methods that can be used for arithmetic
for possibly easier to understand templates.

jvz.


> bob wrote:
> > 
> > Jason says that folks have requested this.
> > 
> > I'm fundamentally opposed (but won't veto it).
> > 
> > But, I'd like to collect use-cases from folks, as to
> > why they think they need arithmetic in a template.
> > 
> > I think we can find Better Solutions than putting
> > math in HTML by a graphic-designer.
> > 
> >         -bob
> > 
> > On Sat, 9 Sep 2000, Jason van Zyl wrote:
> > 
> > > Hey,
> > >
> > > Can we add arithmetic to the template specification.
> > > Arithmetic is parsing fine, so I'd like to add
> > > the functionality to the visitor. Actually I
> > > would have to add the functionality to the
> > > visitor anyway to deal with arithmetic that
> > > happened in conditional expressions like:
> > >
> > > #if (($a + $b) > $c)
> > >
> > > And I propose to use the #set like this:
> > >
> > > #set $foo = 1
> > > #set $foo = $foo + 1
> > > #set $foo = ($a - $b) + $c
> > >
> > > jvz.
> > >
> > > --
> > >
> > > Jason van Zyl
> > > jvanzyl@periapt.com
> > >
> 
> -- Travis Low
>    tlow@iitedge.com
>    1-301-592-6305 (direct)
> 

-- 

Jason van Zyl
jvanzyl@periapt.com

Re: Arithmetic

[Travis Low <tl...@iitedge.com>]

As a graphic artist (turned developer) with 5 years of production art
experience, and 20 years freelance experience, I'd rather you
explained why I DON'T need arithmetic.  Or show me a graphics shop
where there are no rulers or calculators.  Or show me a popular
graphics program that doesn't have little rulers around the display
area.  :-)

Artists have used simple arithmetic since art was invented.

I did post some use cases to the velocity-users list, btw.

Travis

bob wrote:
> 
> Jason says that folks have requested this.
> 
> I'm fundamentally opposed (but won't veto it).
> 
> But, I'd like to collect use-cases from folks, as to
> why they think they need arithmetic in a template.
> 
> I think we can find Better Solutions than putting
> math in HTML by a graphic-designer.
> 
>         -bob
> 
> On Sat, 9 Sep 2000, Jason van Zyl wrote:
> 
> > Hey,
> >
> > Can we add arithmetic to the template specification.
> > Arithmetic is parsing fine, so I'd like to add
> > the functionality to the visitor. Actually I
> > would have to add the functionality to the
> > visitor anyway to deal with arithmetic that
> > happened in conditional expressions like:
> >
> > #if (($a + $b) > $c)
> >
> > And I propose to use the #set like this:
> >
> > #set $foo = 1
> > #set $foo = $foo + 1
> > #set $foo = ($a - $b) + $c
> >
> > jvz.
> >
> > --
> >
> > Jason van Zyl
> > jvanzyl@periapt.com
> >

-- Travis Low
   tlow@iitedge.com
   1-301-592-6305 (direct)

Re: Arithmetic

[bob <bo...@accurev.com>]

Jason says that folks have requested this.

I'm fundamentally opposed (but won't veto it).

But, I'd like to collect use-cases from folks, as to
why they think they need arithmetic in a template.

I think we can find Better Solutions than putting
math in HTML by a graphic-designer.

	-bob

On Sat, 9 Sep 2000, Jason van Zyl wrote:

> Hey,
> 
> Can we add arithmetic to the template specification.
> Arithmetic is parsing fine, so I'd like to add
> the functionality to the visitor. Actually I
> would have to add the functionality to the
> visitor anyway to deal with arithmetic that
> happened in conditional expressions like:
> 
> #if (($a + $b) > $c)
> 
> And I propose to use the #set like this:
> 
> #set $foo = 1
> #set $foo = $foo + 1
> #set $foo = ($a - $b) + $c
> 
> jvz.
> 
> -- 
> 
> Jason van Zyl
> jvanzyl@periapt.com
>