From a63d0ee8fcf3028fb4a3b1b4148d31c6f06dbecc Mon Sep 17 00:00:00 2001
From: Max Kellermann <mk@cm4all.com>
Date: Mon, 3 Feb 2020 20:45:58 +0100
Subject: [PATCH] util/StringView: add method substr()

---
 src/util/StringView.hxx | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/util/StringView.hxx b/src/util/StringView.hxx
index 5be9de3ed..aea2423ec 100644
--- a/src/util/StringView.hxx
+++ b/src/util/StringView.hxx
@@ -88,6 +88,19 @@ struct BasicStringView : ConstBuffer<T> {
 	using ConstBuffer<T>::pop_back;
 	using ConstBuffer<T>::skip_front;
 
+	constexpr BasicStringView<T> substr(size_type pos,
+					    size_type count) const noexcept {
+		return {data + pos, count};
+	}
+
+	constexpr BasicStringView<T> substr(size_type pos) const noexcept {
+		return {data + pos, size - pos};
+	}
+
+	constexpr BasicStringView<T> substr(const char *start) const noexcept {
+		return {start, size_t(data + size - start)};
+	}
+
 	gcc_pure
 	pointer Find(value_type ch) const noexcept {
 		return StringFind(data, ch, this->size);