diff --git a/src/Symfony/Component/ExpressionLanguage/Lexer.php b/src/Symfony/Component/ExpressionLanguage/Lexer.php
index 43bf081746ba0..01ca293018365 100644
--- a/src/Symfony/Component/ExpressionLanguage/Lexer.php
+++ b/src/Symfony/Component/ExpressionLanguage/Lexer.php
@@ -73,7 +73,7 @@ public function tokenize($expression)
                 // strings
                 $tokens[] = new Token(Token::STRING_TYPE, stripcslashes(substr($match[0], 1, -1)), $cursor + 1);
                 $cursor += \strlen($match[0]);
-            } elseif (preg_match('/(?<!\.)not in(?=[\s(])|\!\=\=|(?<!\.)not(?=[\s(])|(?<!\.)and(?=[\s(])|\=\=\=|\>\=|(?<!\.)or(?=[\s(])|\<\=|\*\*|\.\.|(?<!\.)in(?=[\s(])|&&|\|\||(?<!\.)matches|\=\=|\!\=|\*|~|%|\/|\>|\||\!|\^|&|\+|\<|\-/A', $expression, $match, 0, $cursor)) {
+            } elseif (preg_match('/(?<=^|[\s(])not in(?=[\s(])|\!\=\=|(?<=^|[\s(])not(?=[\s(])|(?<=^|[\s(])and(?=[\s(])|\=\=\=|\>\=|(?<=^|[\s(])or(?=[\s(])|\<\=|\*\*|\.\.|(?<=^|[\s(])in(?=[\s(])|&&|\|\||(?<=^|[\s(])matches|\=\=|\!\=|\*|~|%|\/|\>|\||\!|\^|&|\+|\<|\-/A', $expression, $match, 0, $cursor)) {
                 // operators
                 $tokens[] = new Token(Token::OPERATOR_TYPE, $match[0], $cursor + 1);
                 $cursor += \strlen($match[0]);
diff --git a/src/Symfony/Component/ExpressionLanguage/Resources/bin/generate_operator_regex.php b/src/Symfony/Component/ExpressionLanguage/Resources/bin/generate_operator_regex.php
index 03e014200a68c..c86e962526182 100644
--- a/src/Symfony/Component/ExpressionLanguage/Resources/bin/generate_operator_regex.php
+++ b/src/Symfony/Component/ExpressionLanguage/Resources/bin/generate_operator_regex.php
@@ -16,10 +16,10 @@
 $regex = [];
 foreach ($operators as $operator => $length) {
     // Collisions of character operators:
-    // - an operator that begins with a character must not be following after dot
+    // - an operator that begins with a character must have a space or a parenthesis before or starting at the beginning of a string
     // - an operator that ends with a character must be followed by a whitespace or a parenthesis
     $regex[] =
-        (ctype_alpha($operator[$length - 1]) ? '(?<!\.)' : '')
+        (ctype_alpha($operator[0]) ? '(?<=^|[\s(])' : '')
         .preg_quote($operator, '/')
         .(ctype_alpha($operator[$length - 1]) ? '(?=[\s(])' : '');
 }