String interpolation: f or s

Question

I wonder, is there any difference between these two:

val a = 123
println(f"hello1 $a") // 1                         
println(s"hello1 $a") // 2

score 20 · Accepted Answer · edited Jul 10 '17 at 19:08

20

According to the docs, f interpolation is typesafe. Also, it allows to add formatting right after the parameter, which s interpolation doesn't support.

edited Jul 10 '17 at 19:08

Andrii Abramov

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answered Nov 14 '13 at 16:12

Ashalynd

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score 10 · Answer 2 · answered Nov 14 '13 at 16:11

10

The s interpolator allows you to plug in variables or expressions, while the f interpolator allows you to use formatting commands, à la C printf.

Note that contrary to C printf or Java String.format, the f interpolator will typecheck the arguments for you. This link has more information.

answered Nov 14 '13 at 16:11

Philippe

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expressions are supported by `f` too – SuitUp Aug 17 '14 at 14:18

String interpolation: f or s

2 Answers2