[swift-evolution] Change Request: Make myString.hasPrefix("") and myString.hasSuffix("") return true

Guillaume Lessard glessard at tffenterprises.com
Wed Jul 20 15:14:11 CDT 2016

> On 20 juil. 2016, at 12:42, Michael Peternell via swift-evolution <swift-evolution at swift.org> wrote:
> +1
> this should be a bugfix.

First, NSString’s prefix function returns false for empty string parameters, and this would be a significant departure in behaviour.

Second, while an empty string is technically a prefix to any other string, that is hardly ever an interesting answer; it is a trivial solution, just as y=0 is for y(x)=y’(x). It is easy to special-case if one really needs to consider the empty string.

Guillaume Lessard

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