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Edit summary for version 9 :

Version 8

Version 9

Idiom #65 Format decimal number

From real value x in [0,1], create its percentage string representation s with one digit after decimal point. E.g. 0.15625 -> "15.6%"

Idiom #65 Format decimal number

From real value x in [0,1], create its percentage string representation s with one digit after decimal point. E.g. 0.15625 -> "15.6%"

Imports
import std.string : format;
Code
string percent = format("%.1f%%", x * 100.0);