Whiskers template system

1 files changed, 87 insertions, 0 deletions

diff --git a/libdevcore/Whiskers.h b/libdevcore/Whiskers.h
new file mode 100644
index 00000000..21d46af4
--- /dev/null
+++ b/libdevcore/Whiskers.h
@@ -0,0 +1,87 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/** @file Whiskers.h
+ * @author Chris <chis@ethereum.org>
+ * @date 2017
+ *
+ * Moustache-like templates.
+ */
+
+#pragma once
+
+#include <libdevcore/Exceptions.h>
+
+#include <string>
+#include <map>
+#include <vector>
+
+namespace dev
+{
+
+DEV_SIMPLE_EXCEPTION(WhiskersError);
+
+///
+/// Moustache-like templates.
+///
+/// Usage:
+///     std::vector<std::map<std::string, std::string>> listValues(2);
+///     listValues[0]["k"] = "key1";
+///     listValues[0]["v"] = "value1";
+///     listValues[1]["k"] = "key2";
+///     listValues[1]["v"] = "value2";
+///     auto s = Whiskers("<p1>\n<#list><k> -> <v>\n</list>")
+///         ("p1", "HEAD")
+///         ("list", listValues)
+///         .render();
+///
+/// results in s == "HEAD\nkey1 -> value1\nkey2 -> value2\n"
+///
+/// Note that lists cannot themselves contain lists - this would be a future feature.
+class Whiskers
+{
+public:
+	using StringMap = std::map<std::string, std::string>;
+	using StringListMap = std::map<std::string, std::vector<StringMap>>;
+
+	explicit Whiskers(std::string const& _template);
+
+	/// Sets a single parameter, <paramName>.
+	Whiskers& operator()(std::string const& _parameter, std::string const& _value);
+	/// Sets a list parameter, <#listName> </listName>.
+	Whiskers& operator()(
+		std::string const& _listParameter,
+		std::vector<StringMap> const& _values
+	);
+
+	std::string render() const;
+
+private:
+	static std::string replace(
+		std::string const& _template,
+		StringMap const& _parameters,
+		StringListMap const& _listParameters = StringListMap()
+	);
+
+	/// Joins the two maps throwing an exception if two keys are equal.
+	static StringMap joinMaps(StringMap const& _a, StringMap const& _b);
+
+	std::string m_template;
+	StringMap m_parameters;
+	StringListMap m_listParameters;
+};
+
+}