---input---
respond <<HTML 200
<h1>Hello {http.request.uri}</h1>
HTML

---tokens---
'respond'     Keyword
' '           Text.Whitespace
'<<'          Operator
'HTML'        Literal.String.Delimiter
' '           Text.Whitespace
'200'         Literal.Number
'\n'          Text.Whitespace

'<h1>Hello {http.request.uri}</h1>\n' Literal.String.Heredoc

'HTML'        Literal.String.Delimiter
'\n'          Text.Whitespace
