In Javascript, why a space bar “converts” to a number in my code?
-1
Good afternoon!
I have found this code and I am surprised that "backspace" on a keypad converts it to a NUMBER:
let x = null;
x = prompt("Write something: ", "");
if((x == null) || (x == "")) {
alert("Nothing was written");
} else {
if("NaN" == 1*x+"") {
alert("A string was written");
} else {
alert("A number was written");
}
} Why?? And - how to treat it?
And, please, my second question:
there was written let x = null . May I write let x = "" instead? Or only let x?
Many thanks in advance!
javascript
edited Nov 15 '18 at 14:00
Nikos M.
4,54521825
asked Nov 15 '18 at 13:52
JoanJoan
32
|
show 3 more comments
-1
Good afternoon!
I have found this code and I am surprised that "backspace" on a keypad converts it to a NUMBER:
let x = null;
x = prompt("Write something: ", "");
if((x == null) || (x == "")) {
alert("Nothing was written");
} else {
if("NaN" == 1*x+"") {
alert("A string was written");
} else {
alert("A number was written");
}
} Why?? And - how to treat it?
And, please, my second question:
there was written let x = null . May I write let x = "" instead? Or only let x?
Many thanks in advance!
javascript
edited Nov 15 '18 at 14:00
Nikos M.
4,54521825
asked Nov 15 '18 at 13:52
JoanJoan
32
1
stackoverflow.com/questions/9307603/…
– epascarello
Nov 15 '18 at 13:58
What is this supposed to be doing?"NaN" == 1 * x + ""
– Katie.Sun
Nov 15 '18 at 13:58
"And, please, my second question" — Don't ask multiple questions which are unrelated or only tangentially related in a single question. It makes it harder to answer / close as duplicates.
– Quentin
Nov 15 '18 at 13:58
You can set x to "81278127398127312uihkhdkjahdiyqweyqiuyqwkjehqwkjeqwkjeh" and it would not matter.
– epascarello
Nov 15 '18 at 13:58
2
Have you tried debugging your code and see value of x after prompt?
– barbsan
Nov 15 '18 at 14:06
|
show 3 more comments
-1
-1
-1
Good afternoon!
I have found this code and I am surprised that "backspace" on a keypad converts it to a NUMBER:
let x = null;
x = prompt("Write something: ", "");
if((x == null) || (x == "")) {
alert("Nothing was written");
} else {
if("NaN" == 1*x+"") {
alert("A string was written");
} else {
alert("A number was written");
}
} Why?? And - how to treat it?
And, please, my second question:
there was written let x = null . May I write let x = "" instead? Or only let x?
Many thanks in advance!
javascript
edited Nov 15 '18 at 14:00
Nikos M.
4,54521825
asked Nov 15 '18 at 13:52
JoanJoan
32
Good afternoon!
I have found this code and I am surprised that "backspace" on a keypad converts it to a NUMBER:
let x = null;
x = prompt("Write something: ", "");
if((x == null) || (x == "")) {
alert("Nothing was written");
} else {
if("NaN" == 1*x+"") {
alert("A string was written");
} else {
alert("A number was written");
}
} Why?? And - how to treat it?
And, please, my second question:
there was written let x = null . May I write let x = "" instead? Or only let x?
Many thanks in advance!
let x = null;
x = prompt("Write something: ", "");
if((x == null) || (x == "")) {
alert("Nothing was written");
} else {
if("NaN" == 1*x+"") {
alert("A string was written");
} else {
alert("A number was written");
}
} let x = null;
x = prompt("Write something: ", "");
if((x == null) || (x == "")) {
alert("Nothing was written");
} else {
if("NaN" == 1*x+"") {
alert("A string was written");
} else {
alert("A number was written");
}
} javascript
javascript
edited Nov 15 '18 at 14:00
Nikos M.
4,54521825
asked Nov 15 '18 at 13:52
JoanJoan
32
edited Nov 15 '18 at 14:00
Nikos M.
4,54521825
asked Nov 15 '18 at 13:52
JoanJoan
32
edited Nov 15 '18 at 14:00
Nikos M.
4,54521825
edited Nov 15 '18 at 14:00
Nikos M.
4,54521825
edited Nov 15 '18 at 14:00
Nikos M.
4,54521825
4,54521825
asked Nov 15 '18 at 13:52
JoanJoan
32
asked Nov 15 '18 at 13:52
JoanJoan
32
asked Nov 15 '18 at 13:52
JoanJoan
32
32
1
stackoverflow.com/questions/9307603/…
– epascarello
Nov 15 '18 at 13:58
What is this supposed to be doing?"NaN" == 1 * x + ""
– Katie.Sun
Nov 15 '18 at 13:58
"And, please, my second question" — Don't ask multiple questions which are unrelated or only tangentially related in a single question. It makes it harder to answer / close as duplicates.
– Quentin
Nov 15 '18 at 13:58
You can set x to "81278127398127312uihkhdkjahdiyqweyqiuyqwkjehqwkjeqwkjeh" and it would not matter.
– epascarello
Nov 15 '18 at 13:58
2
Have you tried debugging your code and see value of x after prompt?
– barbsan
Nov 15 '18 at 14:06
|
show 3 more comments
1
stackoverflow.com/questions/9307603/…
– epascarello
Nov 15 '18 at 13:58
What is this supposed to be doing?"NaN" == 1 * x + ""
– Katie.Sun
Nov 15 '18 at 13:58
"And, please, my second question" — Don't ask multiple questions which are unrelated or only tangentially related in a single question. It makes it harder to answer / close as duplicates.
– Quentin
Nov 15 '18 at 13:58
You can set x to "81278127398127312uihkhdkjahdiyqweyqiuyqwkjehqwkjeqwkjeh" and it would not matter.
– epascarello
Nov 15 '18 at 13:58
2
Have you tried debugging your code and see value of x after prompt?
– barbsan
Nov 15 '18 at 14:06
1
1
stackoverflow.com/questions/9307603/…
– epascarello
Nov 15 '18 at 13:58
stackoverflow.com/questions/9307603/…
– epascarello
Nov 15 '18 at 13:58
What is this supposed to be doing?
"NaN" == 1 * x + ""– Katie.Sun
Nov 15 '18 at 13:58
What is this supposed to be doing?
"NaN" == 1 * x + ""– Katie.Sun
Nov 15 '18 at 13:58
"And, please, my second question" — Don't ask multiple questions which are unrelated or only tangentially related in a single question. It makes it harder to answer / close as duplicates.
– Quentin
Nov 15 '18 at 13:58
"And, please, my second question" — Don't ask multiple questions which are unrelated or only tangentially related in a single question. It makes it harder to answer / close as duplicates.
– Quentin
Nov 15 '18 at 13:58
You can set x to "81278127398127312uihkhdkjahdiyqweyqiuyqwkjehqwkjeqwkjeh" and it would not matter.
– epascarello
Nov 15 '18 at 13:58
You can set x to "81278127398127312uihkhdkjahdiyqweyqiuyqwkjehqwkjeqwkjeh" and it would not matter.
– epascarello
Nov 15 '18 at 13:58
2
2
Have you tried debugging your code and see value of x after prompt?
– barbsan
Nov 15 '18 at 14:06
Have you tried debugging your code and see value of x after prompt?
– barbsan
Nov 15 '18 at 14:06
|
show 3 more comments
2 Answers
2
active
oldest
votes
-1
let x;
x = prompt("Write something: ", "");
console.log("NaN" == 1); //this will always be false
console.log(1 * x); //x is multiplied by 1 if it is a number
//if x is a letter prints 'NaN'
//if x is null prints 0 because x is converted to a number and when we do this conversion null becomes 0
//if x is empty space also prints zero because when javascript converts " " to a number the result is 0
console.log(x + ""); //x is converted to a string if it is a number, but this essentially just prints the value of x
console.log("NaN" == 1 * x + "");
//because of the order of operations, our first step is to multiply 1 by x
//if x is a space, the result is 0 | 1 * " " = 0
//if x is null, the result is 0 | 1 * null = 0
//if x is a letter, returns NaN | 1 * A = NaN
//if x is a number, returns the number | 1 * 2 = 2
//next we add "" to whatever value we got in the first step
//if the current value of x is 0 we are left with "NaN" == 0, which is false
//if the current value of x is a letter, we are left with "NaN" == "NaN", which is true
//if the current value of x is a number, we are left with "NaN" == *a number* which is false
if ((x === null) || ( x.trim() === "")) { //check if x is empty space
alert("Nothing was written");
} else {
if (Number(x) === "NaN") { //will return true if x contains letters
alert(Number(x));
} else {
alert(Number(x)); //we end up here if x is a number
}
}
Ok, so the above should answer your first question. As for the second, it doesn't matter how you initialize x because on the next line you assign it a value. This value is a String, and JavaScript only tries to convert it to a number once you start doing math with it.
answered Nov 15 '18 at 14:40
Katie.SunKatie.Sun
587114
Who is down voting all of the answers on this page?
– Katie.Sun
Nov 15 '18 at 15:02
Great! This is the only code which does not convert clicking on space bar on keypad (how is it in English: space? blank space? white space?) to a number. And, please, is it possible to alert my own text instead of "NaN"? Because this word never understand a non-programmer and my ideas goes to future. Many thanks for your time :-)
– Joan
Nov 16 '18 at 9:14
@Joan to change the alert text all you would have to do is replace theNumber(x)afterNumber(x) === "NaN"with the text you would want to appear. and yes, in English it's just space.
– Katie.Sun
Nov 16 '18 at 13:40
@Katie.Sun Thanks! Unfortunately the code works curiously: I have only changedalert("A number " +x+ " entered");in the lastelseand since I have the phraseA number...enteredin both of the alerts! Regardless I have entered number or string. For a small explanation: In future, learning much more of Javascript I want to write some simply tasks for my handicaped niece therefore I need to know to write very comprehesible alerts
– Joan
Nov 19 '18 at 8:43
@Katie.Sun Hurrah, I have solved :-) I have only replaced my(x=="")with your(x.trim() === "")and the code works excellently. Bye!
– Joan
Nov 19 '18 at 9:03
add a comment |
-2
In JS, " " == 0 equals true, so when trying to execute + " " end up as + 0
answered Nov 15 '18 at 14:12
AleksWAleksW
1239
1
That's irrelevant. The code in the question never compares a space to zero.
– Quentin
Nov 15 '18 at 16:20
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
-1
let x;
x = prompt("Write something: ", "");
console.log("NaN" == 1); //this will always be false
console.log(1 * x); //x is multiplied by 1 if it is a number
//if x is a letter prints 'NaN'
//if x is null prints 0 because x is converted to a number and when we do this conversion null becomes 0
//if x is empty space also prints zero because when javascript converts " " to a number the result is 0
console.log(x + ""); //x is converted to a string if it is a number, but this essentially just prints the value of x
console.log("NaN" == 1 * x + "");
//because of the order of operations, our first step is to multiply 1 by x
//if x is a space, the result is 0 | 1 * " " = 0
//if x is null, the result is 0 | 1 * null = 0
//if x is a letter, returns NaN | 1 * A = NaN
//if x is a number, returns the number | 1 * 2 = 2
//next we add "" to whatever value we got in the first step
//if the current value of x is 0 we are left with "NaN" == 0, which is false
//if the current value of x is a letter, we are left with "NaN" == "NaN", which is true
//if the current value of x is a number, we are left with "NaN" == *a number* which is false
if ((x === null) || ( x.trim() === "")) { //check if x is empty space
alert("Nothing was written");
} else {
if (Number(x) === "NaN") { //will return true if x contains letters
alert(Number(x));
} else {
alert(Number(x)); //we end up here if x is a number
}
}
Ok, so the above should answer your first question. As for the second, it doesn't matter how you initialize x because on the next line you assign it a value. This value is a String, and JavaScript only tries to convert it to a number once you start doing math with it.
answered Nov 15 '18 at 14:40
Katie.SunKatie.Sun
587114
Who is down voting all of the answers on this page?
– Katie.Sun
Nov 15 '18 at 15:02
Great! This is the only code which does not convert clicking on space bar on keypad (how is it in English: space? blank space? white space?) to a number. And, please, is it possible to alert my own text instead of "NaN"? Because this word never understand a non-programmer and my ideas goes to future. Many thanks for your time :-)
– Joan
Nov 16 '18 at 9:14
@Joan to change the alert text all you would have to do is replace theNumber(x)afterNumber(x) === "NaN"with the text you would want to appear. and yes, in English it's just space.
– Katie.Sun
Nov 16 '18 at 13:40
@Katie.Sun Thanks! Unfortunately the code works curiously: I have only changedalert("A number " +x+ " entered");in the lastelseand since I have the phraseA number...enteredin both of the alerts! Regardless I have entered number or string. For a small explanation: In future, learning much more of Javascript I want to write some simply tasks for my handicaped niece therefore I need to know to write very comprehesible alerts
– Joan
Nov 19 '18 at 8:43
@Katie.Sun Hurrah, I have solved :-) I have only replaced my(x=="")with your(x.trim() === "")and the code works excellently. Bye!
– Joan
Nov 19 '18 at 9:03
add a comment |
-1
let x;
x = prompt("Write something: ", "");
console.log("NaN" == 1); //this will always be false
console.log(1 * x); //x is multiplied by 1 if it is a number
//if x is a letter prints 'NaN'
//if x is null prints 0 because x is converted to a number and when we do this conversion null becomes 0
//if x is empty space also prints zero because when javascript converts " " to a number the result is 0
console.log(x + ""); //x is converted to a string if it is a number, but this essentially just prints the value of x
console.log("NaN" == 1 * x + "");
//because of the order of operations, our first step is to multiply 1 by x
//if x is a space, the result is 0 | 1 * " " = 0
//if x is null, the result is 0 | 1 * null = 0
//if x is a letter, returns NaN | 1 * A = NaN
//if x is a number, returns the number | 1 * 2 = 2
//next we add "" to whatever value we got in the first step
//if the current value of x is 0 we are left with "NaN" == 0, which is false
//if the current value of x is a letter, we are left with "NaN" == "NaN", which is true
//if the current value of x is a number, we are left with "NaN" == *a number* which is false
if ((x === null) || ( x.trim() === "")) { //check if x is empty space
alert("Nothing was written");
} else {
if (Number(x) === "NaN") { //will return true if x contains letters
alert(Number(x));
} else {
alert(Number(x)); //we end up here if x is a number
}
}
Ok, so the above should answer your first question. As for the second, it doesn't matter how you initialize x because on the next line you assign it a value. This value is a String, and JavaScript only tries to convert it to a number once you start doing math with it.
answered Nov 15 '18 at 14:40
Katie.SunKatie.Sun
587114
Who is down voting all of the answers on this page?
– Katie.Sun
Nov 15 '18 at 15:02
Great! This is the only code which does not convert clicking on space bar on keypad (how is it in English: space? blank space? white space?) to a number. And, please, is it possible to alert my own text instead of "NaN"? Because this word never understand a non-programmer and my ideas goes to future. Many thanks for your time :-)
– Joan
Nov 16 '18 at 9:14
@Joan to change the alert text all you would have to do is replace theNumber(x)afterNumber(x) === "NaN"with the text you would want to appear. and yes, in English it's just space.
– Katie.Sun
Nov 16 '18 at 13:40
@Katie.Sun Thanks! Unfortunately the code works curiously: I have only changedalert("A number " +x+ " entered");in the lastelseand since I have the phraseA number...enteredin both of the alerts! Regardless I have entered number or string. For a small explanation: In future, learning much more of Javascript I want to write some simply tasks for my handicaped niece therefore I need to know to write very comprehesible alerts
– Joan
Nov 19 '18 at 8:43
@Katie.Sun Hurrah, I have solved :-) I have only replaced my(x=="")with your(x.trim() === "")and the code works excellently. Bye!
– Joan
Nov 19 '18 at 9:03
add a comment |
-1
-1
-1
let x;
x = prompt("Write something: ", "");
console.log("NaN" == 1); //this will always be false
console.log(1 * x); //x is multiplied by 1 if it is a number
//if x is a letter prints 'NaN'
//if x is null prints 0 because x is converted to a number and when we do this conversion null becomes 0
//if x is empty space also prints zero because when javascript converts " " to a number the result is 0
console.log(x + ""); //x is converted to a string if it is a number, but this essentially just prints the value of x
console.log("NaN" == 1 * x + "");
//because of the order of operations, our first step is to multiply 1 by x
//if x is a space, the result is 0 | 1 * " " = 0
//if x is null, the result is 0 | 1 * null = 0
//if x is a letter, returns NaN | 1 * A = NaN
//if x is a number, returns the number | 1 * 2 = 2
//next we add "" to whatever value we got in the first step
//if the current value of x is 0 we are left with "NaN" == 0, which is false
//if the current value of x is a letter, we are left with "NaN" == "NaN", which is true
//if the current value of x is a number, we are left with "NaN" == *a number* which is false
if ((x === null) || ( x.trim() === "")) { //check if x is empty space
alert("Nothing was written");
} else {
if (Number(x) === "NaN") { //will return true if x contains letters
alert(Number(x));
} else {
alert(Number(x)); //we end up here if x is a number
}
}
Ok, so the above should answer your first question. As for the second, it doesn't matter how you initialize x because on the next line you assign it a value. This value is a String, and JavaScript only tries to convert it to a number once you start doing math with it.
answered Nov 15 '18 at 14:40
Katie.SunKatie.Sun
587114
let x;
x = prompt("Write something: ", "");
console.log("NaN" == 1); //this will always be false
console.log(1 * x); //x is multiplied by 1 if it is a number
//if x is a letter prints 'NaN'
//if x is null prints 0 because x is converted to a number and when we do this conversion null becomes 0
//if x is empty space also prints zero because when javascript converts " " to a number the result is 0
console.log(x + ""); //x is converted to a string if it is a number, but this essentially just prints the value of x
console.log("NaN" == 1 * x + "");
//because of the order of operations, our first step is to multiply 1 by x
//if x is a space, the result is 0 | 1 * " " = 0
//if x is null, the result is 0 | 1 * null = 0
//if x is a letter, returns NaN | 1 * A = NaN
//if x is a number, returns the number | 1 * 2 = 2
//next we add "" to whatever value we got in the first step
//if the current value of x is 0 we are left with "NaN" == 0, which is false
//if the current value of x is a letter, we are left with "NaN" == "NaN", which is true
//if the current value of x is a number, we are left with "NaN" == *a number* which is false
if ((x === null) || ( x.trim() === "")) { //check if x is empty space
alert("Nothing was written");
} else {
if (Number(x) === "NaN") { //will return true if x contains letters
alert(Number(x));
} else {
alert(Number(x)); //we end up here if x is a number
}
}
Ok, so the above should answer your first question. As for the second, it doesn't matter how you initialize x because on the next line you assign it a value. This value is a String, and JavaScript only tries to convert it to a number once you start doing math with it.
answered Nov 15 '18 at 14:40
Katie.SunKatie.Sun
587114
answered Nov 15 '18 at 14:40
Katie.SunKatie.Sun
587114
answered Nov 15 '18 at 14:40
Katie.SunKatie.Sun
587114
answered Nov 15 '18 at 14:40
Katie.SunKatie.Sun
587114
587114
Who is down voting all of the answers on this page?
– Katie.Sun
Nov 15 '18 at 15:02
Great! This is the only code which does not convert clicking on space bar on keypad (how is it in English: space? blank space? white space?) to a number. And, please, is it possible to alert my own text instead of "NaN"? Because this word never understand a non-programmer and my ideas goes to future. Many thanks for your time :-)
– Joan
Nov 16 '18 at 9:14
@Joan to change the alert text all you would have to do is replace theNumber(x)afterNumber(x) === "NaN"with the text you would want to appear. and yes, in English it's just space.
– Katie.Sun
Nov 16 '18 at 13:40
@Katie.Sun Thanks! Unfortunately the code works curiously: I have only changedalert("A number " +x+ " entered");in the lastelseand since I have the phraseA number...enteredin both of the alerts! Regardless I have entered number or string. For a small explanation: In future, learning much more of Javascript I want to write some simply tasks for my handicaped niece therefore I need to know to write very comprehesible alerts
– Joan
Nov 19 '18 at 8:43
@Katie.Sun Hurrah, I have solved :-) I have only replaced my(x=="")with your(x.trim() === "")and the code works excellently. Bye!
– Joan
Nov 19 '18 at 9:03
add a comment |
Who is down voting all of the answers on this page?
– Katie.Sun
Nov 15 '18 at 15:02
Great! This is the only code which does not convert clicking on space bar on keypad (how is it in English: space? blank space? white space?) to a number. And, please, is it possible to alert my own text instead of "NaN"? Because this word never understand a non-programmer and my ideas goes to future. Many thanks for your time :-)
– Joan
Nov 16 '18 at 9:14
@Joan to change the alert text all you would have to do is replace theNumber(x)afterNumber(x) === "NaN"with the text you would want to appear. and yes, in English it's just space.
– Katie.Sun
Nov 16 '18 at 13:40
@Katie.Sun Thanks! Unfortunately the code works curiously: I have only changedalert("A number " +x+ " entered");in the lastelseand since I have the phraseA number...enteredin both of the alerts! Regardless I have entered number or string. For a small explanation: In future, learning much more of Javascript I want to write some simply tasks for my handicaped niece therefore I need to know to write very comprehesible alerts
– Joan
Nov 19 '18 at 8:43
@Katie.Sun Hurrah, I have solved :-) I have only replaced my(x=="")with your(x.trim() === "")and the code works excellently. Bye!
– Joan
Nov 19 '18 at 9:03
Who is down voting all of the answers on this page?
– Katie.Sun
Nov 15 '18 at 15:02
Who is down voting all of the answers on this page?
– Katie.Sun
Nov 15 '18 at 15:02
Great! This is the only code which does not convert clicking on space bar on keypad (how is it in English: space? blank space? white space?) to a number. And, please, is it possible to alert my own text instead of "NaN"? Because this word never understand a non-programmer and my ideas goes to future. Many thanks for your time :-)
– Joan
Nov 16 '18 at 9:14
Great! This is the only code which does not convert clicking on space bar on keypad (how is it in English: space? blank space? white space?) to a number. And, please, is it possible to alert my own text instead of "NaN"? Because this word never understand a non-programmer and my ideas goes to future. Many thanks for your time :-)
– Joan
Nov 16 '18 at 9:14
@Joan to change the alert text all you would have to do is replace the
Number(x) after Number(x) === "NaN" with the text you would want to appear. and yes, in English it's just space.– Katie.Sun
Nov 16 '18 at 13:40
@Joan to change the alert text all you would have to do is replace the
Number(x) after Number(x) === "NaN" with the text you would want to appear. and yes, in English it's just space.– Katie.Sun
Nov 16 '18 at 13:40
@Katie.Sun Thanks! Unfortunately the code works curiously: I have only changed
alert("A number " +x+ " entered"); in the last else and since I have the phrase A number...entered in both of the alerts! Regardless I have entered number or string. For a small explanation: In future, learning much more of Javascript I want to write some simply tasks for my handicaped niece therefore I need to know to write very comprehesible alerts– Joan
Nov 19 '18 at 8:43
@Katie.Sun Thanks! Unfortunately the code works curiously: I have only changed
alert("A number " +x+ " entered"); in the last else and since I have the phrase A number...entered in both of the alerts! Regardless I have entered number or string. For a small explanation: In future, learning much more of Javascript I want to write some simply tasks for my handicaped niece therefore I need to know to write very comprehesible alerts– Joan
Nov 19 '18 at 8:43
@Katie.Sun Hurrah, I have solved :-) I have only replaced my
(x=="") with your (x.trim() === "") and the code works excellently. Bye!– Joan
Nov 19 '18 at 9:03
@Katie.Sun Hurrah, I have solved :-) I have only replaced my
(x=="") with your (x.trim() === "") and the code works excellently. Bye!– Joan
Nov 19 '18 at 9:03
add a comment |
-2
In JS, " " == 0 equals true, so when trying to execute + " " end up as + 0
answered Nov 15 '18 at 14:12
AleksWAleksW
1239
1
That's irrelevant. The code in the question never compares a space to zero.
– Quentin
Nov 15 '18 at 16:20
add a comment |
-2
In JS, " " == 0 equals true, so when trying to execute + " " end up as + 0
answered Nov 15 '18 at 14:12
AleksWAleksW
1239
1
That's irrelevant. The code in the question never compares a space to zero.
– Quentin
Nov 15 '18 at 16:20
add a comment |
-2
-2
-2
In JS, " " == 0 equals true, so when trying to execute + " " end up as + 0
answered Nov 15 '18 at 14:12
AleksWAleksW
1239
In JS, " " == 0 equals true, so when trying to execute + " " end up as + 0
answered Nov 15 '18 at 14:12
AleksWAleksW
1239
edited Nov 20 '18 at 10:12
answered Nov 15 '18 at 14:12
AleksWAleksW
1239
answered Nov 15 '18 at 14:12
AleksWAleksW
1239
answered Nov 15 '18 at 14:12
AleksWAleksW
1239
1239
1
That's irrelevant. The code in the question never compares a space to zero.
– Quentin
Nov 15 '18 at 16:20
add a comment |
1
That's irrelevant. The code in the question never compares a space to zero.
– Quentin
Nov 15 '18 at 16:20
1
1
That's irrelevant. The code in the question never compares a space to zero.
– Quentin
Nov 15 '18 at 16:20
That's irrelevant. The code in the question never compares a space to zero.
– Quentin
Nov 15 '18 at 16:20
add a comment |
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1
stackoverflow.com/questions/9307603/…
– epascarello
Nov 15 '18 at 13:58
What is this supposed to be doing?
"NaN" == 1 * x + ""– Katie.Sun
Nov 15 '18 at 13:58
"And, please, my second question" — Don't ask multiple questions which are unrelated or only tangentially related in a single question. It makes it harder to answer / close as duplicates.
– Quentin
Nov 15 '18 at 13:58
You can set x to "81278127398127312uihkhdkjahdiyqweyqiuyqwkjehqwkjeqwkjeh" and it would not matter.
– epascarello
Nov 15 '18 at 13:58
2
Have you tried debugging your code and see value of x after prompt?
– barbsan
Nov 15 '18 at 14:06