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How to take care that the + before a number is ignored

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Roelof

How to take care that the + before a number is ignored

Hello,

I have a collection that looks like this :

sampleData1
     "comment stating purpose of message"

     ^ #( -8
     +7)

I want to add those numbers up but the code chokes at the +

so I did this :

FrequencyFinderData new class sampleData1   inject: 0 into: [:sum :each
| (each ~= $+) ifTrue: [sum + each asInteger] ]

so when the each is not a + it must count it but still the code chokes
at the +

Where do I think wrong ?

Roelof

HilaireFernandes

Re: How to take care that the + before a number is ignored

Hi Roelof,

Two problems:

1. + is a symbol so compare it to #+

2. A false case is needed to return the untouched sum, otherwise it
truns to nil

#(+1 -8) inject: 0 into: [:sum :each | each ~= #+ ifTrue: [sum + each]
ifFalse: [sum]] .

Hilaire

--
Dr. Geo
http://drgeo.eu

http://drgeo.eu

Pharo Smalltalk Users mailing list

Re: How to take care that the + before a number is ignored

In reply to this post by Roelof

Roeloff,

Is this for the Advent of Code 2018?

The easiest way is to read the input file... Then, I can guide you from there! ;)

-----------------
Benoît St-Jean
Yahoo! Messenger: bstjean
Twitter: @BenLeChialeux
Pinterest: benoitstjean
Instagram: Chef_Benito
IRC: lamneth
Blogue: endormitoire.wordpress.com
"A standpoint is an intellectual horizon of radius zero". (A. Einstein)

On Sunday, December 2, 2018, 4:49:06 a.m. EST, Roelof Wobben <[hidden email]> wrote:

Hello,

I have a collection that looks like this :

sampleData1

"comment stating purpose of message"

^ #( -8

+7)

I want to add those numbers up but the code chokes at the +

so I did this :

FrequencyFinderData new class sampleData1 inject: 0 into: [:sum :each

| (each ~= $+) ifTrue: [sum + each asInteger] ]

so when the each is not a + it must count it but still the code chokes

at the +

Where do I think wrong ?

Roelof

Re: How to take care that the + before a number is ignored

In reply to this post by HilaireFernandes

Op 2-12-2018 om 11:15 schreef Hilaire:
> #(+1 -8) inject: 0 into: [:sum :each | each ~= #+ ifTrue: [sum + each]
> ifFalse: [sum]] .

Thanks,

Now to stretch my mind I will try to make one with double-dispatch.

Roelof

Roelof

Re: How to take care that the + before a number is ignored

In reply to this post by Pharo Smalltalk Users mailing list

Op 2-12-2018 om 11:43 schreef Benoit St-Jean via Pharo-users:

if you can learn me that.
Right now., the input is a method.

I think I can do the rest from there

Pharo Smalltalk Users mailing list

Re: How to take care that the + before a number is ignored

In reply to this post by Roelof

You're giving yourself *A LOT* of trouble by not simply reading a file! Besides, you'll have the same problem for every problem, twice per problem!

On Sunday, December 2, 2018, 5:46:21 a.m. EST, Roelof Wobben <[hidden email]> wrote:

Roelof

Pharo Smalltalk Users mailing list

Re: How to take care that the + before a number is ignored

In reply to this post by Roelof

Do you want the solution for the first one to get you going?

The part2 of problem 1 is somewhat a little more complex but once you get the idea, the rest shouldn't be that hard!

On Sunday, December 2, 2018, 5:50:30 a.m. EST, Roelof Wobben <[hidden email]> wrote:

Op 2-12-2018 om 11:43 schreef Benoit St-Jean via Pharo-users:

if you can learn me that.
Right now., the input is a method.

I think I can do the rest from there

Roelof

Re: How to take care that the + before a number is ignored

Op 2-12-2018 om 11:55 schreef Benoit St-Jean via Pharo-users:

Nope, only the part how I can read the file.

Roelof

Pharo Smalltalk Users mailing list

Re: How to take care that the + before a number is ignored

You can do solve the problem without the "lines" variable but, believe me, you want to keep those lines in a collection. It's gonna be a lot easier down the road!

Hint (to solve the problem) : look at what "lines" contain (instances of which class). That class has everything you need to parse those '+2' and '-8' ... ;)

| file |

lines := OrderedCollection new.

file := StandardFileStream readOnlyFileNamed: 'day.1.input'.
[file atEnd] whileFalse: [lines add: file nextLine].

file close.

On Sunday, December 2, 2018, 6:09:42 a.m. EST, Roelof Wobben <[hidden email]> wrote:

Op 2-12-2018 om 11:55 schreef Benoit St-Jean via Pharo-users:

Nope, only the part how I can read the file.

Roelof

Pharo Smalltalk Users mailing list

Re: How to take care that the + before a number is ignored

In reply to this post by Roelof

Oups!

Usually, it's way nicer/better/suggested to declare all variables... Forgot "lines" !

Nicer version:

| file lines |

lines := OrderedCollection new.

file := StandardFileStream readOnlyFileNamed: 'day.1.input'.
[file atEnd] whileFalse: [lines add: file nextLine].
file close.

On Sunday, December 2, 2018, 6:09:42 a.m. EST, Roelof Wobben <[hidden email]> wrote:

Op 2-12-2018 om 11:55 schreef Benoit St-Jean via Pharo-users:

Nope, only the part how I can read the file.

Roelof

Sven Van Caekenberghe-2

Re: How to take care that the + before a number is ignored

In reply to this post by Roelof

> On 2 Dec 2018, at 12:07, Roelof Wobben <[hidden email]> wrote:
>
> Nope, only the part how I can read the file.

For scripting (non-production) code, you can read the whole file (and split it into lines) using

'file.log' asFileReference contents lines.

Sven Van Caekenberghe-2

Re: How to take care that the + before a number is ignored

In reply to this post by Pharo Smalltalk Users mailing list

> On 2 Dec 2018, at 12:14, Benoit St-Jean via Pharo-users <[hidden email]> wrote:
>
>
> From: Benoit St-Jean <[hidden email]>
> Subject: Re: [Pharo-users] How to take care that the + before a number is ignored
> Date: 2 December 2018 at 12:14:10 GMT+1
> To: [hidden email]
> Reply-To: Benoit St-Jean <[hidden email]>
>
>
> You can do solve the problem without the "lines" variable but, believe me, you want to keep those lines in a collection. It's gonna be a lot easier down the road!
>
> Hint (to solve the problem) : look at what "lines" contain (instances of which class). That class has everything you need to parse those '+2' and '-8' ... ;)
>
>
> | file |
>
> lines := OrderedCollection new.
>
> file := StandardFileStream readOnlyFileNamed: 'day.1.input'.

That is a deprecated class in Pharo 7.

> [file atEnd] whileFalse: [lines add: file nextLine].
> file close.

Here is a better way:

Array streamContents: [ :lines |
'file.log' asFileReference readStreamDo: [ :in |
[ in atEnd ] whileFalse: [ lines nextPut: in nextLine ] ] ]

> -----------------
> Benoît St-Jean
> Yahoo! Messenger: bstjean
> Twitter: @BenLeChialeux
> Pinterest: benoitstjean
> Instagram: Chef_Benito
> IRC: lamneth
> Blogue: endormitoire.wordpress.com
> "A standpoint is an intellectual horizon of radius zero". (A. Einstein)
>
>
> On Sunday, December 2, 2018, 6:09:42 a.m. EST, Roelof Wobben <[hidden email]> wrote:
>
>
> Op 2-12-2018 om 11:55 schreef Benoit St-Jean via Pharo-users:
>
> Nope, only the part how I can read the file.
>
>
> Roelof
>
>
>
>

Roelof

Re: How to take care that the + before a number is ignored

In reply to this post by Pharo Smalltalk Users mailing list

Op 2-12-2018 om 12:19 schreef Benoit St-Jean via Pharo-users:

oke, and if I understand your code files is then the variable that holds
the file.

Roelof

Pharo Smalltalk Users mailing list

Re: How to take care that the + before a number is ignored

Exactly!

It's easier to manipulate that OrderedCollection that to open/reopen the file. It'll be VERY handy for problem #2 where you will need to iterate multiple times on the data! ;)

On Sunday, December 2, 2018, 7:15:06 a.m. EST, Roelof Wobben <[hidden email]> wrote:

Op 2-12-2018 om 12:19 schreef Benoit St-Jean via Pharo-users:

oke, and if I understand your code files is then the variable that holds

the file.

Roelof

Pharo Smalltalk Users mailing list

Re: How to take care that the + before a number is ignored

In reply to this post by Sven Van Caekenberghe-2

Wasn't sure, I'm on Squeak right now!! loll

On Sunday, December 2, 2018, 6:26:12 a.m. EST, Sven Van Caekenberghe <[hidden email]> wrote:

Ben Coman

Re: How to take care that the + before a number is ignored

In reply to this post by Roelof

On Sun, 2 Dec 2018 at 17:49, Roelof Wobben <[hidden email]> wrote:

Hello,

I have a collection that looks like this :

sampleData1
     "comment stating purpose of message"

     ^ #( -8
     +7)

I want to add those numbers up but the code chokes at the +

To get some insight, do....

#( -8 +7) inspect

You will notice three elements when I think you expected two.

So perhaps you need...

x := #( -8 +7) reject: [:y | y = #+].

and then #inject:into: "x"

cheers -ben

so I did this :

FrequencyFinderData new class sampleData1 inject: 0 into: [:sum :each
| (each ~= $+) ifTrue: [sum + each asInteger] ]

so when the each is not a + it must count it but still the code chokes
at the +

Where do I think wrong ?

Roelof

Pharo Smalltalk Users mailing list

Re: How to take care that the + before a number is ignored

In reply to this post by Pharo Smalltalk Users mailing list

I am not using a file, but copy/paste my puzzleInput into a puzzleInput method.

Then I use lines from there.

e.g. shifts

^ self puzzleInput lines collect: [ :each | ((each beginsWith: '+') ifTrue: [ each allButFirst ] ifFalse: [ each ]) asNumber ]

Because the challenge is personalized and it is annoying to have to commit a supplementary file in the github repository.

Phil

On Sun, Dec 2, 2018 at 3:27 PM Benoit St-Jean via Pharo-users <[hidden email]> wrote:

Exactly!

It's easier to manipulate that OrderedCollection that to open/reopen the file. It'll be VERY handy for problem #2 where you will need to iterate multiple times on the data! ;)

-----------------
Benoît St-Jean
Yahoo! Messenger: bstjean
Twitter: @BenLeChialeux
Pinterest: benoitstjean
Instagram: Chef_Benito
IRC: lamneth
Blogue: endormitoire.wordpress.com
"A standpoint is an intellectual horizon of radius zero". (A. Einstein)

On Sunday, December 2, 2018, 7:15:06 a.m. EST, Roelof Wobben <[hidden email]> wrote:

Op 2-12-2018 om 12:19 schreef Benoit St-Jean via Pharo-users:

oke, and if I understand your code files is then the variable that holds

the file.

Roelof

Roelof

Re: How to take care that the + before a number is ignored

Again a memory message?

Op 2 december 2018 om 17:06 schreef phil--- via Pharo-users <[hidden email]>:

Pharo Smalltalk Users mailing list

Re: How to take care that the + before a number is ignored

In reply to this post by Pharo Smalltalk Users mailing list

Just realized that String>>#asNumber works differently in Pharo and in Squeak.

'+3' asNumber "Works in Squeak, not in Pharo"

BUT

'+3' asInteger "Works in both Squeak and Pharo"

On Sunday, December 2, 2018, 11:06:56 a.m. EST, [hidden email] <[hidden email]> wrote:

I am not using a file, but copy/paste my puzzleInput into a puzzleInput method.

Then I use lines from there.

e.g. shifts

^ self puzzleInput lines collect: [ :each | ((each beginsWith: '+') ifTrue: [ each allButFirst ] ifFalse: [ each ]) asNumber ]

Because the challenge is personalized and it is annoying to have to commit a supplementary file in the github repository.

Phil

On Sun, Dec 2, 2018 at 3:27 PM Benoit St-Jean via Pharo-users <[hidden email]> wrote:

Exactly!

It's easier to manipulate that OrderedCollection that to open/reopen the file. It'll be VERY handy for problem #2 where you will need to iterate multiple times on the data! ;)

-----------------
Benoît St-Jean
Yahoo! Messenger: bstjean
Twitter: @BenLeChialeux
Pinterest: benoitstjean
Instagram: Chef_Benito
IRC: lamneth
Blogue: endormitoire.wordpress.com
"A standpoint is an intellectual horizon of radius zero". (A. Einstein)

On Sunday, December 2, 2018, 7:15:06 a.m. EST, Roelof Wobben <[hidden email]> wrote:

Op 2-12-2018 om 12:19 schreef Benoit St-Jean via Pharo-users:

oke, and if I understand your code files is then the variable that holds

the file.

Roelof

Richard O'Keefe

Re: How to take care that the + before a number is ignored

In reply to this post by Roelof

Thinking about this functionally, you want

   to sum

   the array elements that are not + .

So,

   (array select: [:each | each ~~ #+]) sum

The *best* approach is not to put the + symbols

into the array in the first place.

On Sun, 2 Dec 2018 at 23:46, Roelof Wobben <[hidden email]> wrote:

Op 2-12-2018 om 11:15 schreef Hilaire:
> #(+1 -8) inject: 0 into: [:sum :each | each ~= #+ ifTrue: [sum + each]
> ifFalse: [sum]] .

Thanks,

Now to stretch my mind I will try to make one with double-dispatch.

Roelof