Re: [Pharo-users] min:max:

April 21, 2018

      Looking at senders of #min:max:, I found in BitBlt>>roundNumbers the following:

               destX := destX asInteger 

                              min: maxVal

                              max: minVal.

Which seems to summarize the illogicality very well.

However, note that PetitParser, PetitParser2 and Magritte all implement #min:max: as a method to set upper and lower limits, and there the meaning is the logical one. It all looks a mess.

Peter Kenny

From: Pharo-users <pharo-users-bounces@lists.pharo.org> On Behalf Of Ben Coman
Sent: 21 April 2018 02:16
To: Any question about pharo is welcome <pharo-users@lists.pharo.org>; The general-purpose Squeak developers list <squeak-dev@lists.squeakfoundation.org>
Subject: Re: [Pharo-users] min:max:

On 21 April 2018 at 03:51, Hilaire <hilaire@drgeo.eu <mailto:hilaire@drgeo.eu> > wrote:

Hi,

Out of curiosity.

I always found the #min:max: confusing and lost in its expressiveness.

One should write:

    10 min: 48 max: 12

to expect 12.

but logically one (at least me) may want to express it as:

    10 min: 12 max: 48

Then when reading its source code, it is even more confusing:

min: aMin max: aMax
    ^ (self min: aMin) max: aMax

Are not the argument names inversed in their meaning, if any?

I would agree.  I see most use by Color like...

    Color>>adjustBrightness: brightness

        "Adjust the relative brightness of this color. (lowest value is 0.005 so that hue information is not lost)"

        ^ self class

                h: self hue

                s: self saturation

                v: (self brightness + brightness min: 1.0 max: 0.005)

                alpha: self alpha

Trying to read that twists my brain.  

I can understand the intent from the implementation 

min: aMin max: aMax 

               ^ (self min: aMin) max: aMax

but that message might more properly be  #min:thenMax:

However something like    

    (self brightness + brightness boundedBy: 0.005 and: 1.0)

    (self brightness + brightness boundedMin: 0.005 max: 1.0) 

seems more intention revealing.

Altering  #min:max  semantics would make awful portability,

but perhaps it should forward to a new method to make it clear the other is preferred.

Would the Squeak community be amenable to a similar change?

I'd be happy to contribute the changes to the Squeak Inbox.

cheers -ben

Re: [Pharo-users] min:max:

PBKResearch