diff --git a/src/Escaper.php b/src/Escaper.php
index <HASH>..<HASH> 100644
--- a/src/Escaper.php
+++ b/src/Escaper.php
@@ -43,7 +43,7 @@ class Escaper
 	*/
 	public function escapeCharacterClass(string $char): string
 	{
-		return (isset($this->inCharacterClass[$char])) ? $this->inCharacterClass[$char] : $char;
+		return $this->inCharacterClass[$char] ?? $char;
 	}
 
 	/**
@@ -54,6 +54,6 @@ class Escaper
 	*/
 	public function escapeLiteral(string $char): string
 	{
-		return (isset($this->inLiteral[$char])) ? $this->inLiteral[$char] : $char;
+		return $this->inLiteral[$char] ?? $char;
 	}
 }
\ No newline at end of file
diff --git a/src/Output/PrintableAscii.php b/src/Output/PrintableAscii.php
index <HASH>..<HASH> 100644
--- a/src/Output/PrintableAscii.php
+++ b/src/Output/PrintableAscii.php
@@ -43,7 +43,7 @@ abstract class PrintableAscii extends BaseImplementation
 	{
 		$table = [9 => '\\t', 10 => '\\n', 13 => '\\r'];
 
-		return (isset($table[$cp])) ? $table[$cp] : $this->escapeAscii($cp);
+		return $table[$cp] ?? $this->escapeAscii($cp);
 	}
 
 	/**
Replaced ternaries with null coalescing operator