One line if statement not working
Remove if
from if @item.rigged ? "Yes" : "No"
Ternary operator has form condition ? if_true : if_false
Putting a simple if-then-else statement on one line
That's more specifically a ternary operator expression than an if-then, here's the python syntax
value_when_true if condition else value_when_false
Better Example: (thanks Mr. Burns)
'Yes' if fruit == 'Apple' else 'No'
Now with assignment and contrast with if syntax
fruit = 'Apple'
isApple = True if fruit == 'Apple' else False
vs
fruit = 'Apple'
isApple = False
if fruit == 'Apple' : isApple = True
One line if else statement refuses to work
You have to provide else
clause as well for this one liner. Following line will work:
print(BDF) if header is 1 else None
Java one line if does not work for prints
condition ? System.out.println("true") : System.out.println("false");
is not a statement.
From here:
In computer science, a ternary operator is an operator that takes three arguments.
System.out.println("true")
does not qualify to be an argument, as the method println()
is of void type. Hence, it is not a statement.
Use this instead:
System.out.println(condition ? "true" : "false");
Python: Why if-else oneline statement does not work with continue in else?
Because continue
is a statement, not an expression.
x = foo if bar else baz
is meant to produce a value and then bind x
to that value. For that to be possible, foo
, bar
and baz
need to be things that can be evaluated (expressions).
What should x
become in the case of
x = foo if False else continue
?
Right...
Single line if statement in reduce statement not working
The main reason it's not working is because your ternary operation returns a number in both scenarios. .push()
returns the length
of the array and not the array itself.
So you can change it to use concat
:
const arr = [ 'tasselled', 'black', 'low-top', 'lace-up' ]const output = arr.reduce((a,e,i) => e.includes('lace') ? a.concat(i) : a, []);
console.log(output)
One line if/else in JavaScript
You want a ternary operator:
properties['Value'] = (IsItMuted === true) ? 'On' : 'Off';
The ? :
is called a ternary operator and acts just like an if
/else
when used in an expression.
Javascript one line If...else...else if statement
Sure, you can do nested ternary operators but they are hard to read.
var variable = (condition) ? (true block) : ((condition2) ? (true block2) : (else block2))
if statement in R can only have one line?
To be precise, this is not about lines but about statements. You can have the whole if else
statement in one line:
> if (TRUE) 1 else 3
[1] 1
A statement will end at the end of the line (if complete), you can see that nicely in interactive mode if you enter the code line by line:
> if (TRUE)
+ 1
[1] 1
> else
Fehler: Unerwartete(s) 'else' in "else" # error: unexpected 'else' in "else"
> 3
[1] 3
if
can come in form if (condition) statement
or if (condition) statement else other.statement
, the interpreter assumes the first version is meant if the statement is complete after line 2 - in interactive mode it cannot sensibly wait whether an else
appears next. This is different in source
d code - there it is clear with the next line which form it is.
Semicolons end statements as well:
> if (TRUE) 1; else 3
[1] 1
Fehler: Unerwartete(s) 'else' in " else" # error: unexpected 'else' in "else"
But you can only have one statement in each branch of the condition.
> if (TRUE) 1; 2 else 3
[1] 1
Fehler: Unerwartete(s) 'else' in " 2 else" # error: unexpected 'else' in "2 else"
Curly braces group statements so they appear as one statement.
> if (TRUE) {1; 2} else 3
[1] 2
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