diff --git a/boot/lexer.ll b/boot/lexer.ll
index 941b66c..2ad3ffd 100644
--- a/boot/lexer.ll
+++ b/boot/lexer.ll
@@ -107,16 +107,16 @@ false                   {
 nil                     {
                             return yy::parser::make_NIL(this->location);
                         }
-and                     {
+\&                      {
                             return yy::parser::make_AND(this->location);
                         }
 xor                     {
                             return yy::parser::make_XOR(this->location);
                         }
-or                      {
+\|                      {
                             return yy::parser::make_OR(this->location);
                         }
-not                     {
+\~                      {
                             return yy::parser::make_NOT(this->location);
                         }
 return                  {
diff --git a/source.elna b/source.elna
index f04657f..f6e3400 100644
--- a/source.elna
+++ b/source.elna
@@ -198,22 +198,22 @@ end
 
 proc is_digit(c: Char) -> Bool;
 begin
-  return cast(c: Int) >= cast('0': Int) and cast(c: Int) <= cast('9': Int)
+  return cast(c: Int) >= cast('0': Int) & cast(c: Int) <= cast('9': Int)
 end
 
 proc is_alpha(c: Char) -> Bool;
 begin
-  return cast(c: Int) >= cast('A': Int) and cast(c: Int) <= cast('z': Int)
+  return cast(c: Int) >= cast('A': Int) & cast(c: Int) <= cast('z': Int)
 end
 
 proc is_alnum(c: Char) -> Bool;
 begin
-  return is_digit(c) or is_alpha(c)
+  return is_digit(c) | is_alpha(c)
 end
 
 proc is_space(c: Char) -> Bool;
 begin
-  return c = ' ' or c = '\n' or c = '\t'
+  return c = ' ' | c = '\n' | c = '\t'
 end
 
 proc substring(string: String, start: Word, count: Word) -> String;
@@ -398,12 +398,12 @@ end
 
 proc source_code_expect(source_code: ^SourceCode, expected: Char) -> Bool;
 begin
-  return not source_code_empty(source_code) and source_code_head(source_code^) = expected
+  return ~source_code_empty(source_code) & source_code_head(source_code^) = expected
 end
 
 proc skip_spaces(source_code: ^SourceCode);
 begin
-  while not source_code_empty(source_code) and is_space(source_code_head(source_code^)) do
+  while ~source_code_empty(source_code) & is_space(source_code_head(source_code^)) do
     if source_code_head(source_code^) = '\n' then
       source_code_break(source_code)
 	end;
@@ -413,14 +413,14 @@ end
 
 proc is_ident(char: Char) -> Bool;
 begin
-  return is_alnum(char) or char = '_'
+  return is_alnum(char) | char = '_'
 end
 
 proc lex_identifier(source_code: ^SourceCode, token_content: ^StringBuffer);
 var
   content_length: Word
 begin
-  while not source_code_empty(source_code) and is_ident(source_code_head(source_code^)) do
+  while ~source_code_empty(source_code) & is_ident(source_code_head(source_code^)) do
     string_buffer_push(token_content, source_code_head(source_code^));
 	source_code_advance(source_code)
   end
@@ -432,11 +432,11 @@ var
 begin
   trailing := 0u;
 
-  while not source_code_empty(source_code) and trailing < 2u do
+  while ~source_code_empty(source_code) & trailing < 2u do
     if source_code_head(source_code^) = '*' then
 	  string_buffer_push(token_content, '*');
 	  trailing := 1u
-	elsif source_code_head(source_code^) = ')' and trailing = 1u then
+	elsif source_code_head(source_code^) = ')' & trailing = 1u then
       string_buffer_pop(token_content, 1u);
 	  trailing := 2u
 	else
@@ -453,13 +453,13 @@ proc lex_character(source_code: ^SourceCode, token_content: ^Char) -> Bool;
 var
   successful: Bool
 begin
-  successful := not source_code_empty(source_code);
+  successful := ~source_code_empty(source_code);
 
   if successful then
     if source_code_head(source_code^) = '\\' then
       source_code_advance(source_code);
 
-      successful := not source_code_empty(source_code) and escape_char(source_code_head(source_code^), token_content)
+      successful := ~source_code_empty(source_code) & escape_char(source_code_head(source_code^), token_content)
 	else
       token_content^ := source_code_head(source_code^);
 	  successful := true
@@ -480,7 +480,7 @@ var
 begin
   is_valid := true;
 
-  while is_valid and not source_code_empty(source_code) and source_code_head(source_code^) <> '"' do
+  while is_valid & ~source_code_empty(source_code) & source_code_head(source_code^) <> '"' do
     is_valid := lex_character(source_code, @next_char);
 
     if is_valid then
@@ -488,7 +488,7 @@ begin
     end
   end;
 
-  if is_valid and source_code_expect(source_code, '"') then
+  if is_valid & source_code_expect(source_code, '"') then
     source_code_advance(source_code)
   else
     is_valid := false
@@ -500,7 +500,7 @@ proc lex_number(source_code: ^SourceCode, token_content: ^Int);
 begin
   token_content^ := 0;
 
-  while not source_code_empty(source_code) and is_digit(source_code_head(source_code^)) do
+  while ~source_code_empty(source_code) & is_digit(source_code_head(source_code^)) do
     token_content^ := token_content^ * 10 + (cast(source_code_head(source_code^): Int) - cast('0': Int));
 
     source_code_advance(source_code)
@@ -738,12 +738,12 @@ begin
 
   skip_spaces(@source_code);
 
-  while not source_code_empty(@source_code) do
+  while ~source_code_empty(@source_code) do
 	tokens := cast(reallocarray(cast(tokens: ^Byte), tokens_size^ + 1u, #size(Token)): ^Token);
     current_token := tokens + tokens_size^;
 	first_char := source_code_head(source_code);
 
-    if is_alpha(first_char) or first_char = '_' then
+    if is_alpha(first_char) | first_char = '_' then
       lex_identifier(@source_code, @token_buffer);
       current_token^ := categorize_identifier(string_buffer_clear(@token_buffer))
 	elsif is_digit(first_char) then
@@ -778,7 +778,7 @@ begin
 	elsif first_char = '\'' then
       source_code_advance(@source_code);
 
-	  if lex_character(@source_code, @current_token^.value.char_value) and source_code_expect(@source_code, '\'') then
+	  if lex_character(@source_code, @current_token^.value.char_value) & source_code_expect(@source_code, '\'') then
 	  	current_token^.kind := TOKEN_CHARACTER;
 	    source_code_advance(@source_code)
 	  else