Whiskers template system

1 files changed, 127 insertions, 0 deletions

diff --git a/libdevcore/Whiskers.cpp b/libdevcore/Whiskers.cpp
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+++ b/libdevcore/Whiskers.cpp
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+/*
+	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.cpp
+ * @author Chris <chis@ethereum.org>
+ * @date 2017
+ *
+ * Moustache-like templates.
+ */
+
+#include <libdevcore/Whiskers.h>
+
+#include <libdevcore/Assertions.h>
+
+#include <boost/regex.hpp>
+
+using namespace std;
+using namespace dev;
+
+Whiskers::Whiskers(string const& _template):
+m_template(_template)
+{
+}
+
+Whiskers& Whiskers::operator ()(string const& _parameter, string const& _value)
+{
+	assertThrow(
+		m_parameters.count(_parameter) == 0,
+		WhiskersError,
+		_parameter + " already set."
+	);
+	assertThrow(
+		m_listParameters.count(_parameter) == 0,
+		WhiskersError,
+		_parameter + " already set as list parameter."
+	);
+	m_parameters[_parameter] = _value;
+
+	return *this;
+}
+
+Whiskers& Whiskers::operator ()(
+	string const& _listParameter,
+	vector<map<string, string>> const& _values
+)
+{
+	assertThrow(
+		m_listParameters.count(_listParameter) == 0,
+		WhiskersError,
+		_listParameter + " already set."
+	);
+	assertThrow(
+		m_parameters.count(_listParameter) == 0,
+		WhiskersError,
+		_listParameter + " already set as value parameter."
+	);
+	m_listParameters[_listParameter] = _values;
+
+	return *this;
+}
+
+string Whiskers::render() const
+{
+	return replace(m_template, m_parameters, m_listParameters);
+}
+
+string Whiskers::replace(
+	string const& _template,
+	StringMap const& _parameters,
+	map<string, vector<StringMap>> const& _listParameters
+)
+{
+	using namespace boost;
+	static regex listOrTag("<([^#/>]+)>|<#([^>]+)>(.*?)</\\2>");
+	return regex_replace(_template, listOrTag, [&](match_results<string::const_iterator> _match) -> string
+	{
+		string tagName(_match[1]);
+		if (!tagName.empty())
+		{
+			assertThrow(_parameters.count(tagName), WhiskersError, "Tag " + tagName + " not found.");
+			return _parameters.at(tagName);
+		}
+		else
+		{
+			string listName(_match[2]);
+			string templ(_match[3]);
+			assertThrow(!listName.empty(), WhiskersError, "");
+			assertThrow(
+				_listParameters.count(listName),
+				WhiskersError, "List parameter " + listName + " not set."
+			);
+			string replacement;
+			for (auto const& parameters: _listParameters.at(listName))
+				replacement += replace(templ, joinMaps(_parameters, parameters));
+			return replacement;
+		}
+	});
+}
+
+Whiskers::StringMap Whiskers::joinMaps(
+	Whiskers::StringMap const& _a,
+	Whiskers::StringMap const& _b
+)
+{
+	Whiskers::StringMap ret = _a;
+	for (auto const& x: _b)
+		assertThrow(
+			ret.insert(x).second,
+			WhiskersError,
+			"Parameter collision"
+		);
+	return ret;
+}
+