From 924a8fff6bc517519eb91ca73adf06505b3f5a87 Mon Sep 17 00:00:00 2001
From: Alex Beregszaszi <alex@rtfs.hu>
Date: Tue, 14 Feb 2017 14:24:25 +0000
Subject: Fix exponentional notation in number literals

---
 Changelog.md              |  1 +
 libsolidity/ast/Types.cpp | 31 +++++++++++++++++++++++++++----
 2 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/Changelog.md b/Changelog.md
index 212d84fa..4135a3b7 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -5,6 +5,7 @@ Features:
  * Introduce ``.transfer(value)`` for sending Ether.
  * Code generator: Support ``revert()`` to abort with rolling back, but not consuming all gas.
  * Inline assembly: Support ``revert`` (EIP140) as an opcode.
+ * Parser: Support scientific notation in numbers (e.g. ``2e8`` and ``200e-2``).
  * Type system: Support explicit conversion of external function to address.
 
 Bugfixes:
diff --git a/libsolidity/ast/Types.cpp b/libsolidity/ast/Types.cpp
index d2793b6d..aecf830d 100644
--- a/libsolidity/ast/Types.cpp
+++ b/libsolidity/ast/Types.cpp
@@ -576,11 +576,31 @@ tuple<bool, rational> RationalNumberType::isValidLiteral(Literal const& _literal
 	rational x;
 	try
 	{
-		rational numerator;
-		rational denominator(1);
-		
+		auto expPoint = find(_literal.value().begin(), _literal.value().end(), 'e');
+		if (expPoint == _literal.value().end())
+			expPoint = find(_literal.value().begin(), _literal.value().end(), 'E');
 		auto radixPoint = find(_literal.value().begin(), _literal.value().end(), '.');
-		if (radixPoint != _literal.value().end())
+
+		if (expPoint != _literal.value().end())
+		{
+			if (
+				!all_of(_literal.value().begin(), expPoint, ::isdigit) ||
+				!all_of(expPoint + 1, _literal.value().end(), ::isdigit)
+			)
+				return make_tuple(false, rational(0));
+
+			bigint exp = bigint(string(expPoint + 1, _literal.value().end()));
+
+			if (exp > numeric_limits<int32_t>::max() || exp < numeric_limits<int32_t>::min())
+				return make_tuple(false, rational(0));
+
+			x = bigint(string(_literal.value().begin(), expPoint));
+			x *= boost::multiprecision::pow(
+				bigint(10),
+				exp.convert_to<int32_t>()
+			);
+		}
+		else if (radixPoint != _literal.value().end())
 		{
 			if (
 				!all_of(radixPoint + 1, _literal.value().end(), ::isdigit) || 
@@ -594,6 +614,9 @@ tuple<bool, rational> RationalNumberType::isValidLiteral(Literal const& _literal
 				[](char const& a) { return a == '0'; }
 			);
 
+			rational numerator;
+			rational denominator(1);
+
 			denominator = bigint(string(fractionalBegin, _literal.value().end()));
 			denominator /= boost::multiprecision::pow(
 				bigint(10), 
-- 
cgit