The Daily WTF: Curious Perversions in Information Technology

darkmatter · 2014-07-11 Reply Admin

It also doesn't quite do exactly the same thing, so if you really needed array_key_exists(), you better not try to subsititute isset() for it.

Filed Under: not that we've been burned by that shit where I work.... that's totally not why I know this.

ben_lubar · 2014-07-11 Reply Admin

darkmatter:
It also doesn't quite do exactly the same thing, so if you really needed array_key_exists(), you better not try to subsititute isset() for it.

isset returns false in all cases that array_key_exists returns false, so you could just do if isset || array_key_exists to get the performance without making your code easy to read or changing its meaning.

darkmatter · 2014-07-11 Reply Admin

Except in the one circumstance that I recall, that specifically wasn't what we wanted. We needed the true case, which only array_key_exists would tell us. (or the other way around.... I'm not going to try to go look it up, it wasn't even my project, I just got asked the question by someone else saying "wtf is going on?")

edit - though that is interesting to think about - i'll have to keep in mind the next time I'm in PHP. Thankfully we're moving towards all .NET (C#)

darkmatter · 2014-07-11 Reply Admin

Hm. Further thinking makes me wonder, if it's 10x better to do isset() than array_key_exists(), then perhaps I should have my colleague use your logic every time, in the cases where the isset() is expected to take precedence at least 10%+ of the time.

I always used isset() anyways, because I didn't allow the 1 case that array_key_exists() works instead to even happen.

ben_lubar · 2014-07-11 Reply Admin

package main

import "testing"

const size = 100000

var array = make(map[int]*struct{})

func init() {
        for i := 0; i < size; i++ {
                switch i % 3 {
                case 0:
                        array[i] = nil
                case 1:
                        array[i] = new(struct{})
                case 2:
                        // not set
                }
        }
}

func isset(i int) bool {
        return array[i] != nil
}

func array_key_exists(i int) bool {
        _, ok := array[i]
        return ok
}

func BenchmarkIsset(b *testing.B) {
        for i := 0; i < b.N; i += size {
                for j := 0; j < size; j++ {
                        _ = isset(j)
                }
        }
}

func BenchmarkAKE(b *testing.B) {
        for i := 0; i < b.N; i += size {
                for j := 0; j < size; j++ {
                        _ = array_key_exists(j)
                }
        }
}

func BenchmarkIAKE(b *testing.B) {
        for i := 0; i < b.N; i += size {
                for j := 0; j < size; j++ {
                        _ = isset(j) || array_key_exists(j)
                }
        }
}

func BenchmarkAKEI(b *testing.B) {
        for i := 0; i < b.N; i += size {
                for j := 0; j < size; j++ {
                        _ = array_key_exists(j) || isset(j)
                }
        }
}

BenchmarkIsset  50000000                57.6 ns/op
BenchmarkAKE    50000000                57.0 ns/op
BenchmarkIAKE   20000000                83.6 ns/op
BenchmarkAKEI   50000000                69.8 ns/op

In Go, isset and array_key_exists are equivalent in speed, and 57.6ns is probably about the time it takes to execute a comment in PHP.

nomdeplume · 2014-07-11 Reply Admin

foo AKA fooo:
CigarDoug:
2. Please provide a one line example that is BETTER at expressing "0 carrots", "1 carrot", "2 carrots". Seriously. I really want to know a better way to do this. Ternary solutions, used sparingly, can be quite elegant.
printf (ngettext ("%i carrot", "%i carrots", n), n);

But what if you have a negative or fractional number of carrots?

Nagesh · 2014-07-11 Reply Admin

darkmatter:
Thankfully we're moving towards all .NET (C#)

You could be happy if you use Python or RoR. Personally I am making preference of python, but I have heard that RoR is equally good if not better.

Captain · 2014-07-11 Reply Admin

Which framework are you using? I like Ruby, the language, better. But Python is a fine language. Ruby on Rails is definitely full of good features. Django is pretty good too.

Nagesh · 2014-07-11 Reply Admin

I am working in ASP .NET with C#. Some good day I am using MVC. Right now my assignment is related to Salesforce.com I have ot create some stuff in Salesforce.com I am learning to insert jquery in my Visual Force page.

Almost missed java servlets. That is where the reporting application is.

chubertdev · 2014-07-11 Reply Admin

Nagesh:
I am working in ASP .NET with C#. Some good day I am using MVC. Right now my assignment is related to Salesforce.com I have ot create some stuff in Salesforce.com I am learning to insert jquery in my Visual Force page.
Almost missed java servlets. That is where the reporting application is.

Why do I get the feeling that the project at my last company is being outsourced to you?

Captain · 2014-07-11 Reply Admin

Because you work with extremely common tools in a well understood domain and are therefore a fungible commodity.

chubertdev · 2014-07-11 Reply Admin

Captain:
Because you work with extremely common tools in a well understood domain and are therefore a fungible commodity.

Yeah, but some of the specifics to SFDC have hit home (not just limited to the above comment).

Nagesh · 2014-07-11 Reply Admin

chubertdev:
Yeah, but some of the specifics to SFDC have hit home (not just limited to the above comment).

Scary scary scary. PM me with your real life name and client name.

chubertdev · 2014-07-11 Reply Admin

Nagesh:
Scary scary scary. PM me with your real life name and client name.

There should be only one San Diego company that would outsource its SFDC work.

2014-07-14 Reply Admin

"The only practical application of ternary operator is to either intentionally obfuscate your code or use it as a soapbox to brag about how "l33t" you are."

This could be said of pretty much any element of any programming language, if you don't ever use that element. While I agree that this particular instance is hard to read, it doesn't invalidate the code itself. Besides, I fail to see how this is any better:

if (FailSafe == 0) {
	return 'No technical alarms';
} elsif ((FailSafe & 1) != 0 && (FailSafe & 2) != 0 && (FailSafe & 4) != 0 && (FailSafe & 8) != 0) {
	return 'Detection zones staying in a given state; Bad visibility; Initialization; Bad configuration';
} elsif ((FailSafe & 1) != 0 && (FailSafe & 2) != 0 && (FailSafe & 4) != 0) {
	return 'Detection zones staying in a given state; Bad visibility; Initialization';
} elsif ((FailSafe & 1) != 0 && (FailSafe & 2) != 0 && (FailSafe & 8) != 0) {
	return 'Detection zones staying in a given state; Bad visibility; Bad configuration';
} elsif ((FailSafe & 1) != 0 && (FailSafe & 4) != 0 && (FailSafe & 8) != 0) {
	return 'Detection zones staying in a given state; Initialization; Bad configuration';
} elsif ((FailSafe & 2) != 0 && (FailSafe & 4) != 0 && (FailSafe & 8) != 0) {
	return 'Bad visibility; Initialization; Bad configuration';
} elsif ((FailSafe & 1) != 0 && (FailSafe & 2) != 0) {
	return 'Detection zones staying in a given state; Bad visibility';
} elsif ((FailSafe & 1) != 0 && (FailSafe&4) != 0) {
	return {'Detection zones staying in a given state; Initialization';
} elsif ((FailSafe & 1) != 0 && (FailSafe & 8) != 0) {
	return { 'Detection zones staying in a given state; Bad configuration';
} elsif ((FailSafe & 2) != 0 && (FailSafe & 4) !=0) {
	return 'Bad visibility; Initialization';
} elsif ((FailSafe & 2) != 0 && (FailSafe & 8) != 0) {
	return 'Bad visibility; Bad configuration';
} elsif ((FailSafe & 4) != 0 && (FailSafe & 8) != 0) {
	return 'Initialization; Bad configuration';
} elsif ((FailSafe & 1) != 0) {
	return 'Detection zones staying in a given state';
} elsif ((FailSafe & 2) != 0) {
	return 'Bad visibility';
} elsif ((FailSafe & 4) != 0) {
	return 'Initialization';
} elsif ((FailSafe & 8) != 0) {
	return 'Bad configuration';
} else {
	return 'Unknown';
}

urkerab · 2014-07-14 Reply Admin

There are several places that need ternaries where a plain old if won't do; constexpr functions and member initialisers come to mind. One of the most esoteric uses I heard of though was in macro programming where you wrote f(true ? any_type() : ARG) which resulted in templating f over the type of ARG without actually evaluating ARG. (Nowadays you probably just write f<decltype(ARG)>() instead.)

If I really wanted to use ternary operators, rather than the neat array that @Zecc used, I would write it something like this:

FailSafe & 8 ?
  FailSafe & 4 ?
     FailSafe & 2 ?
        FailSafe & 1 ?
          'Detection zones staying in a given state; Bad visibility; Initialization; Bad configuration' :
          'Bad visibility; Initialization; Bad configuration' :
        FailSafe & 1 ?
          'Detection zones staying in a given state; Initialization; Bad configuration' :
          'Initialization; Bad configuration' :
     FailSafe & 2 ?
        FailSafe & 1 ?
          'Detection zones staying in a given state; Bad visibility; Bad configuration' :
          'Bad visibility; Bad configuration' :
        FailSafe & 1 ?
          'Detection zones staying in a given state; Bad configuration' :
          'Bad configuration' ?
  FailSafe & 4 ?
     FailSafe & 2 ?
        FailSafe & 1 ?
          'Detection zones staying in a given state; Bad visibility; Initialization' :
          'Bad visibility; Initialization' :
        FailSafe & 1 ?
          'Detection zones staying in a given state; Initialization' :
          'Initialization' :
     FailSafe & 2 ?
        FailSafe & 1 ?
          'Detection zones staying in a given state; Bad visibility' :
          'Bad visibility' :
        FailSafe & 1 ?
          'Detection zones staying in a given state' :
          'No technical alarms'

Captain · 2014-07-14 Reply Admin

Um, ? is right associative.

Zecc · 2014-07-14 Reply Admin

Works for me in both JS and C (after replacing the quotes).

Captain · 2014-07-14 Reply Admin

Yes, it would "work". But it's utterly unreadable. It effectively treats the operator as left associative. In that case, you might as well collapse it to:

if (FailSafe & 8) { (errors.append "error 8"); }
if (FailSafe & 4) { (errors.append "error 4"); }
if (FailSafe & 2) { (errors.append "error 2"); }
if (FailSafe & 1) { (errors.append "error 1"); }

and use some sensible data structures.

ben_lubar · 2014-07-15 Reply Admin

http://what.thedailywtf.com/badges/128/someone-didn-t-get-the-joke

PJH · 2014-07-15 Reply Admin

Oh, alright then...

boomzilla · 2014-07-15 Reply Admin

Who among us has not deserved this at some time?

Maciejasjmj · 2014-07-15 Reply Admin

boomzilla:
Who among us has not deserved this at some time?

Given the likes of @Nagesh and @SpectateSwamp on this forum, perhaps we all do.

Me, I'm still waiting for mine.

PJH · 2014-07-15 Reply Admin

Maciejasjmj:
Me, I'm still waiting for mine.

I'm waiting for feedback from upstream.

darkmatter · 2014-07-15 Reply Admin

Maciejasjmj:
Me, I'm still waiting for mine.

Damn you... I never got one, I assume because it was too easy for @PJH to fix the CSS, making it a weak Dicsourse configuration flaw.

Maciejasjmj · 2014-07-15 Reply Admin

Speaking of Discourse...

https://meta.discourse.org/t/invisible-topic-is-not-invisible/17603

Find one bug, get one free!

PJH · 2014-07-15 Reply Admin

darkmatter:
Damn you... I never got one, I assume because it was too easy for @PJH to fix the CSS, making it a weak Dicsourse configuration flaw.

I do get distracted occasionally...

darkmatter · 2014-07-15 Reply Admin

PJH:
I do get distracted occasionally...

oo badger badger... Thanks for validating my existence!

Captain · 2014-07-15 Reply Admin

My proudest TDWTF moment.

M_Adams · 2014-07-16 Reply Admin

Which is easier to read?:

my $salute;
if ($name eq $EMPTY_STR) {
    $salute = 'Dear Customer';
}
elsif ($name =~ m/\A ((?:Sir|Dame) \s+ \S+)/xms) {
    $salute = "Dear $1";
}

elsif ($name =~ m/([^\n]*), \s+ Ph[.]?D \z/xms) {
    $sa1ute = "Dear Dr $1";
}
else {
    $salute = "Dear $name";
}

Versus a "tabular ternary" (note the comments):


           # Name format...                            # Salutation...
my $salute = $name eq $EMPTY_STR                       ? 'Dear Customer'
           : $name =~ m/ \A((?:Sir|Dame) \s+ \S+) /xms ? "Dear $1"
           : $name =~ m/ (.*), \s+ Ph[.]?D \z     /xms ? "Dear Dr $1"
           :                                             "Dear $name"
           ;

Just another example of how people can't write legible or maintainable code.

Arantor · 2014-07-16 Reply Admin

Don't get started on British PHP:

perchance (£name is equal to £EMPTY_STR) {
    £salute = 'Dear Customer';
} otherwise, perchance (perl_regular_expression_match(..toolazy.., £matches) {
    £salute = 'Dear ' . £matches[1];
}

M_Adams · 2014-07-16 Reply Admin

Just realized I bufu'd the "Dear Dr" regex on the rewrite to the tabular version:

: $name =~ m/ (.*), \s+ Ph[.]?D \z /xms ? "Dear Dr $1"

Should be:

: $name =~ m/ ([^\n]*), \s+ Ph[.]?D \z /xms ? "Dear Dr $1"

the (.*) under /s grabs newlines where the ([^\n]*) grabs anything but newlines...

Moral : Definitely require code reviews after refactoring!

Arantor · 2014-07-16 Reply Admin

How many strokes is that in golf exactly?

M_Adams · 2014-07-16 Reply Admin

Weeell... removing extraneous (auto-format-able type) white space: 262→215 = -47 :)

Zecc · 2014-07-16 Reply Admin

M_Adams:
```perl $sa1ute```

Nice try.

Filed under: broken quote

M_Adams · 2014-07-16 Reply Admin

Ding Ding Ding! We have a winner on the "Easter Egg" hunt :)

urkerab · 2014-07-22 Reply Admin

Yes, I was assuming a sane language. I suppose in PHP I would have had to wrap everything in parentheses making it as ugly as the original article.

One Bad Ternary Operator Deserves Another

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