diff --git a/WordPress/Sniff.php b/WordPress/Sniff.php
index e688876d45..1509de45b7 100644
--- a/WordPress/Sniff.php
+++ b/WordPress/Sniff.php
@@ -389,6 +389,19 @@ abstract class Sniff implements PHPCS_Sniff {
 		'sanitize_key' => true,
 	);
 
+	/**
+	 * Token which when they preceed code indicate the value is safely casted.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @var array
+	 */
+	protected $safe_casts = array(
+		\T_INT_CAST    => true,
+		\T_DOUBLE_CAST => true,
+		\T_BOOL_CAST   => true,
+	);
+
 	/**
 	 * Functions that format strings.
 	 *
@@ -1560,8 +1573,12 @@ protected function is_safe_casted( $stackPtr ) {
 			true
 		);
 
+		if ( false === $prev ) {
+			return false;
+		}
+
 		// Check if it is a safe cast.
-		return \in_array( $this->tokens[ $prev ]['code'], array( \T_INT_CAST, \T_DOUBLE_CAST, \T_BOOL_CAST ), true );
+		return isset( $this->safe_casts[ $this->tokens[ $prev ]['code'] ] );
 	}
 
 	/**