diff --git a/src/parser.rs b/src/parser.rs
index 721c83c..93aa830 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -254,7 +254,8 @@ impl<'a> Parser<'a> {
             Some((pos, 't')) |
             Some((pos, 'f')) => self.boolean(pos),
             Some((pos, '[')) => self.array(pos),
-            Some((pos, '-')) => self.number_or_datetime(pos),
+            Some((pos, '-')) |
+            Some((pos, '+')) => self.number_or_datetime(pos),
             Some((pos, ch)) if ch.is_digit(10) => self.number_or_datetime(pos),
             _ => {
                 let mut it = self.cur.clone();
@@ -453,8 +454,8 @@ impl<'a> Parser<'a> {
         return Some(Value::String(ret));
     }
 
-    fn number_or_datetime(&mut self, start: usize) -> Option<Value> {
-        let negative = self.eat('-');
+    fn number_or_datetime(&mut self, mut start: usize) -> Option<Value> {
+        let sign = if self.eat('+') { start += 1; true } else {self.eat('-')};
         let mut is_float = false;
         loop {
             match self.cur.clone().next() {
@@ -473,7 +474,7 @@ impl<'a> Parser<'a> {
             } else {
                 self.input.slice(start, end).parse().map(Float)
             }
-        } else if !negative && self.eat('-') {
+        } else if !sign && self.eat('-') {
             self.datetime(start, end + 1)
         } else {
             self.input.slice(start, end).parse().map(Integer)
diff --git a/tests/valid/example-v0.3.0.json b/tests/valid/example-v0.3.0.json
index 490b5dc..1d9dcb5 100644
--- a/tests/valid/example-v0.3.0.json
+++ b/tests/valid/example-v0.3.0.json
@@ -1 +1 @@
-{"Array":{"key1":{"type":"array","value":[{"type":"integer","value":"1"},{"type":"integer","value":"2"},{"type":"integer","value":"3"}]},"key2":{"type":"array","value":[{"type":"string","value":"red"},{"type":"string","value":"yellow"},{"type":"string","value":"green"}]},"key3":{"type":"array","value":[{"type":"array","value":[{"type":"integer","value":"1"},{"type":"integer","value":"2"}]},{"type":"array","value":[{"type":"integer","value":"3"},{"type":"integer","value":"4"},{"type":"integer","value":"5"}]}]},"key4":{"type":"array","value":[{"type":"array","value":[{"type":"integer","value":"1"},{"type":"integer","value":"2"}]},{"type":"array","value":[{"type":"string","value":"a"},{"type":"string","value":"b"},{"type":"string","value":"c"}]}]},"key5":{"type":"array","value":[{"type":"integer","value":"1"},{"type":"integer","value":"2"},{"type":"integer","value":"3"}]},"key6":{"type":"array","value":[{"type":"integer","value":"1"},{"type":"integer","value":"2"}]}},"Booleans":{"False":{"type":"bool","value":"false"},"True":{"type":"bool","value":"true"}},"Datetime":{"key1":{"type":"datetime","value":"1979-05-27T07:32:00Z"}},"Float":{"both":{},"exponent":{},"fractional":{"key2":{"type":"float","value":"3.1415"},"key3":{"type":"float","value":"-0.01"}}},"Integer":{"key2":{"type":"integer","value":"42"},"key3":{"type":"integer","value":"0"},"key4":{"type":"integer","value":"-17"}},"String":{"Literal":{"Multiline":{"lines":{"type":"string","value":"The first newline is\ntrimmed in raw strings.\n   All other whitespace\n   is preserved.\n"},"regex2":{"type":"string","value":"I [dw]on't need \\d{2} apples"}},"quoted":{"type":"string","value":"Tom \"Dubs\" Preston-Werner"},"regex":{"type":"string","value":"\u003c\\i\\c*\\s*\u003e"},"winpath":{"type":"string","value":"C:\\Users\\nodejs\\templates"},"winpath2":{"type":"string","value":"\\\\ServerX\\admin$\\system32\\"}},"Multiline":{"key1":{"type":"string","value":"One\nTwo"},"key2":{"type":"string","value":"One\nTwo"},"key3":{"type":"string","value":"One\nTwo"}},"Multilined":{"Singleline":{"key1":{"type":"string","value":"The quick brown fox jumps over the lazy dog."},"key2":{"type":"string","value":"The quick brown fox jumps over the lazy dog."},"key3":{"type":"string","value":"The quick brown fox jumps over the lazy dog."}}},"basic":{"type":"string","value":"I'm a string. \"You can quote me\". Name\u0009José\nLocation\u0009SF."}},"Table":{"key":{"type":"string","value":"value"}},"dog":{"tater":{"type":{"type":"string","value":"pug"}}},"fruit":[{"name":{"type":"string","value":"apple"},"physical":{"color":{"type":"string","value":"red"},"shape":{"type":"string","value":"round"}},"variety":[{"name":{"type":"string","value":"red delicious"}},{"name":{"type":"string","value":"granny smith"}}]},{"name":{"type":"string","value":"banana"},"variety":[{"name":{"type":"string","value":"plantain"}}]}],"products":[{"name":{"type":"string","value":"Hammer"},"sku":{"type":"integer","value":"738594937"}},{},{"color":{"type":"string","value":"gray"},"name":{"type":"string","value":"Nail"},"sku":{"type":"integer","value":"284758393"}}],"x":{"y":{"z":{"w":{}}}}}
+{"Array":{"key1":{"type":"array","value":[{"type":"integer","value":"1"},{"type":"integer","value":"2"},{"type":"integer","value":"3"}]},"key2":{"type":"array","value":[{"type":"string","value":"red"},{"type":"string","value":"yellow"},{"type":"string","value":"green"}]},"key3":{"type":"array","value":[{"type":"array","value":[{"type":"integer","value":"1"},{"type":"integer","value":"2"}]},{"type":"array","value":[{"type":"integer","value":"3"},{"type":"integer","value":"4"},{"type":"integer","value":"5"}]}]},"key4":{"type":"array","value":[{"type":"array","value":[{"type":"integer","value":"1"},{"type":"integer","value":"2"}]},{"type":"array","value":[{"type":"string","value":"a"},{"type":"string","value":"b"},{"type":"string","value":"c"}]}]},"key5":{"type":"array","value":[{"type":"integer","value":"1"},{"type":"integer","value":"2"},{"type":"integer","value":"3"}]},"key6":{"type":"array","value":[{"type":"integer","value":"1"},{"type":"integer","value":"2"}]}},"Booleans":{"False":{"type":"bool","value":"false"},"True":{"type":"bool","value":"true"}},"Datetime":{"key1":{"type":"datetime","value":"1979-05-27T07:32:00Z"}},"Float":{"both":{},"exponent":{},"fractional":{"key1":{"type":"float","value":"1.0"},"key2":{"type":"float","value":"3.1415"},"key3":{"type":"float","value":"-0.01"}}},"Integer":{"key1":{"type":"integer","value":"99"},"key2":{"type":"integer","value":"42"},"key3":{"type":"integer","value":"0"},"key4":{"type":"integer","value":"-17"}},"String":{"Literal":{"Multiline":{"lines":{"type":"string","value":"The first newline is\ntrimmed in raw strings.\n   All other whitespace\n   is preserved.\n"},"regex2":{"type":"string","value":"I [dw]on't need \\d{2} apples"}},"quoted":{"type":"string","value":"Tom \"Dubs\" Preston-Werner"},"regex":{"type":"string","value":"\u003c\\i\\c*\\s*\u003e"},"winpath":{"type":"string","value":"C:\\Users\\nodejs\\templates"},"winpath2":{"type":"string","value":"\\\\ServerX\\admin$\\system32\\"}},"Multiline":{"key1":{"type":"string","value":"One\nTwo"},"key2":{"type":"string","value":"One\nTwo"},"key3":{"type":"string","value":"One\nTwo"}},"Multilined":{"Singleline":{"key1":{"type":"string","value":"The quick brown fox jumps over the lazy dog."},"key2":{"type":"string","value":"The quick brown fox jumps over the lazy dog."},"key3":{"type":"string","value":"The quick brown fox jumps over the lazy dog."}}},"basic":{"type":"string","value":"I'm a string. \"You can quote me\". Name\u0009José\nLocation\u0009SF."}},"Table":{"key":{"type":"string","value":"value"}},"dog":{"tater":{"type":{"type":"string","value":"pug"}}},"fruit":[{"name":{"type":"string","value":"apple"},"physical":{"color":{"type":"string","value":"red"},"shape":{"type":"string","value":"round"}},"variety":[{"name":{"type":"string","value":"red delicious"}},{"name":{"type":"string","value":"granny smith"}}]},{"name":{"type":"string","value":"banana"},"variety":[{"name":{"type":"string","value":"plantain"}}]}],"products":[{"name":{"type":"string","value":"Hammer"},"sku":{"type":"integer","value":"738594937"}},{},{"color":{"type":"string","value":"gray"},"name":{"type":"string","value":"Nail"},"sku":{"type":"integer","value":"284758393"}}],"x":{"y":{"z":{"w":{}}}}}
diff --git a/tests/valid/example-v0.3.0.toml b/tests/valid/example-v0.3.0.toml
index 3e39d62..76aacc3 100644
--- a/tests/valid/example-v0.3.0.toml
+++ b/tests/valid/example-v0.3.0.toml
@@ -79,7 +79,7 @@ trimmed in raw strings.
 # Negative numbers are prefixed with a minus sign.
 
 [Integer]
-#key1 = +99
+key1 = +99
 key2 = 42
 key3 = 0
 key4 = -17
@@ -91,7 +91,7 @@ key4 = -17
 [Float.fractional]
 
 # fractional
-#key1 = +1.0
+key1 = +1.0
 key2 = 3.1415
 key3 = -0.01