▲ 696 ▼ the hardest exam question (lemmy.ml) submitted 2 years ago by siriusmart@lemmy.ml to c/programmerhumor@lemmy.ml 137 comments fedilink hide all child comments
[–] Skullgrid@lemmy.world 11 points 2 years ago (3 children) NaN is of type number. because fuck me. permalink fedilink source parent hideshow 6 child comments replies: [–] kevincox@lemmy.ml 10 points 2 years ago To be fair, this is actually reasonable. But it does look stupid on the face of it. permalink fedilink source parent [–] zea_64@lemmy.blahaj.zone 9 points 2 years ago IEEE-754 permalink fedilink source parent [–] joneskind@lemmy.world 1 point 2 years ago* (1 child) When my console throws a NaN I kinda think of it as an Halloween kid receiving a fruit instead of a candy. They won’t say “That’s a fruit”. They’ll say “That’s not a treat”. I’m personally pissed more often by a falsy 0. Did you know that early analog computers would literally explode when asked to divide by 0? Now computers just say “Hey stupid, that shit is not even a Number in a mathematical sense, but sure I’ll add one to it.” instead of “Why would you kill me like this?” You can’t really define Infinity as a number, yet it is part of their world. So typeof NaN === ‘number’ totally makes sense in that regard. If you ever worked with arrays of dates, don’t judge NaN too harshly. permalink fedilink source parent hideshow 2 child comments replies: [–] Skullgrid@lemmy.world 1 point 2 years ago (1 child) Falsy zero? What's wrong with that, 1 is true and 0 is false. I thought that was standard logic? permalink fedilink source parent hideshow 2 child comments replies: [–] joneskind@lemmy.world 1 point 2 years ago (1 child) in javascript a property is truthy if it exists myThing.property = "some string" if (myThing.property) { // true // do something } It works with everything except of course for falsy values myThing.number = someNumberThatShouldNotBeEqualToZero if (myThing.number) { // do something very important with that number that should not be equal to zero } // This can fail at anytime without warning So you've got to be extra careful with that logic when you're dealing with numbers. I am not saying it's wrong though. I'm saying it's often annoying. permalink fedilink source parent hideshow 2 child comments replies: [–] Skullgrid@lemmy.world 1 point 2 years ago (1 child) ah ok , I think I write this a bit more verbose when using other languages, instead of if(thing) { stuff; } I do if(thing != null) { stuff; } so checking for numbers being truthy & existing didn't seem like an issue permalink fedilink source parent hideshow 2 child comments replies: [–] joneskind@lemmy.world 1 point 2 years ago* In the case of a non-existing property, the value would be undefined rather than null. And while == and != exist in JavaScript, most linters will throw an error and require a === and !== instead as they should be avoided. null == undefined // true null === undefined // false Besides, null is a perfectly valid value for a property, just as 0. Working with API Platform, I couldn't tell the number of times I used this kind of statement: if (property || property === null) { // do some stuff } Probably just as much as if (property || property === 0) { // do some stuff } permalink fedilink source parent
[–] kevincox@lemmy.ml 10 points 2 years ago To be fair, this is actually reasonable. But it does look stupid on the face of it. permalink fedilink source parent
[–] joneskind@lemmy.world 1 point 2 years ago* (1 child) When my console throws a NaN I kinda think of it as an Halloween kid receiving a fruit instead of a candy. They won’t say “That’s a fruit”. They’ll say “That’s not a treat”. I’m personally pissed more often by a falsy 0. Did you know that early analog computers would literally explode when asked to divide by 0? Now computers just say “Hey stupid, that shit is not even a Number in a mathematical sense, but sure I’ll add one to it.” instead of “Why would you kill me like this?” You can’t really define Infinity as a number, yet it is part of their world. So typeof NaN === ‘number’ totally makes sense in that regard. If you ever worked with arrays of dates, don’t judge NaN too harshly. permalink fedilink source parent hideshow 2 child comments replies: [–] Skullgrid@lemmy.world 1 point 2 years ago (1 child) Falsy zero? What's wrong with that, 1 is true and 0 is false. I thought that was standard logic? permalink fedilink source parent hideshow 2 child comments replies: [–] joneskind@lemmy.world 1 point 2 years ago (1 child) in javascript a property is truthy if it exists myThing.property = "some string" if (myThing.property) { // true // do something } It works with everything except of course for falsy values myThing.number = someNumberThatShouldNotBeEqualToZero if (myThing.number) { // do something very important with that number that should not be equal to zero } // This can fail at anytime without warning So you've got to be extra careful with that logic when you're dealing with numbers. I am not saying it's wrong though. I'm saying it's often annoying. permalink fedilink source parent hideshow 2 child comments replies: [–] Skullgrid@lemmy.world 1 point 2 years ago (1 child) ah ok , I think I write this a bit more verbose when using other languages, instead of if(thing) { stuff; } I do if(thing != null) { stuff; } so checking for numbers being truthy & existing didn't seem like an issue permalink fedilink source parent hideshow 2 child comments replies: [–] joneskind@lemmy.world 1 point 2 years ago* In the case of a non-existing property, the value would be undefined rather than null. And while == and != exist in JavaScript, most linters will throw an error and require a === and !== instead as they should be avoided. null == undefined // true null === undefined // false Besides, null is a perfectly valid value for a property, just as 0. Working with API Platform, I couldn't tell the number of times I used this kind of statement: if (property || property === null) { // do some stuff } Probably just as much as if (property || property === 0) { // do some stuff } permalink fedilink source parent
[–] Skullgrid@lemmy.world 1 point 2 years ago (1 child) Falsy zero? What's wrong with that, 1 is true and 0 is false. I thought that was standard logic? permalink fedilink source parent hideshow 2 child comments replies: [–] joneskind@lemmy.world 1 point 2 years ago (1 child) in javascript a property is truthy if it exists myThing.property = "some string" if (myThing.property) { // true // do something } It works with everything except of course for falsy values myThing.number = someNumberThatShouldNotBeEqualToZero if (myThing.number) { // do something very important with that number that should not be equal to zero } // This can fail at anytime without warning So you've got to be extra careful with that logic when you're dealing with numbers. I am not saying it's wrong though. I'm saying it's often annoying. permalink fedilink source parent hideshow 2 child comments replies: [–] Skullgrid@lemmy.world 1 point 2 years ago (1 child) ah ok , I think I write this a bit more verbose when using other languages, instead of if(thing) { stuff; } I do if(thing != null) { stuff; } so checking for numbers being truthy & existing didn't seem like an issue permalink fedilink source parent hideshow 2 child comments replies: [–] joneskind@lemmy.world 1 point 2 years ago* In the case of a non-existing property, the value would be undefined rather than null. And while == and != exist in JavaScript, most linters will throw an error and require a === and !== instead as they should be avoided. null == undefined // true null === undefined // false Besides, null is a perfectly valid value for a property, just as 0. Working with API Platform, I couldn't tell the number of times I used this kind of statement: if (property || property === null) { // do some stuff } Probably just as much as if (property || property === 0) { // do some stuff } permalink fedilink source parent
[–] joneskind@lemmy.world 1 point 2 years ago (1 child) in javascript a property is truthy if it exists myThing.property = "some string" if (myThing.property) { // true // do something } It works with everything except of course for falsy values myThing.number = someNumberThatShouldNotBeEqualToZero if (myThing.number) { // do something very important with that number that should not be equal to zero } // This can fail at anytime without warning So you've got to be extra careful with that logic when you're dealing with numbers. I am not saying it's wrong though. I'm saying it's often annoying. permalink fedilink source parent hideshow 2 child comments replies: [–] Skullgrid@lemmy.world 1 point 2 years ago (1 child) ah ok , I think I write this a bit more verbose when using other languages, instead of if(thing) { stuff; } I do if(thing != null) { stuff; } so checking for numbers being truthy & existing didn't seem like an issue permalink fedilink source parent hideshow 2 child comments replies: [–] joneskind@lemmy.world 1 point 2 years ago* In the case of a non-existing property, the value would be undefined rather than null. And while == and != exist in JavaScript, most linters will throw an error and require a === and !== instead as they should be avoided. null == undefined // true null === undefined // false Besides, null is a perfectly valid value for a property, just as 0. Working with API Platform, I couldn't tell the number of times I used this kind of statement: if (property || property === null) { // do some stuff } Probably just as much as if (property || property === 0) { // do some stuff } permalink fedilink source parent
[–] Skullgrid@lemmy.world 1 point 2 years ago (1 child) ah ok , I think I write this a bit more verbose when using other languages, instead of if(thing) { stuff; } I do if(thing != null) { stuff; } so checking for numbers being truthy & existing didn't seem like an issue permalink fedilink source parent hideshow 2 child comments replies: [–] joneskind@lemmy.world 1 point 2 years ago* In the case of a non-existing property, the value would be undefined rather than null. And while == and != exist in JavaScript, most linters will throw an error and require a === and !== instead as they should be avoided. null == undefined // true null === undefined // false Besides, null is a perfectly valid value for a property, just as 0. Working with API Platform, I couldn't tell the number of times I used this kind of statement: if (property || property === null) { // do some stuff } Probably just as much as if (property || property === 0) { // do some stuff } permalink fedilink source parent
[–] joneskind@lemmy.world 1 point 2 years ago* In the case of a non-existing property, the value would be undefined rather than null. And while == and != exist in JavaScript, most linters will throw an error and require a === and !== instead as they should be avoided. null == undefined // true null === undefined // false Besides, null is a perfectly valid value for a property, just as 0. Working with API Platform, I couldn't tell the number of times I used this kind of statement: if (property || property === null) { // do some stuff } Probably just as much as if (property || property === 0) { // do some stuff } permalink fedilink source parent
