Merge pull request #25 from UAVCAN/service-response-marker

Grammar updates per the Spec review suggestions

Author: pavel-kirienko

pydsdl/_test.py

@@ -143,7 +143,7 @@ def _unittest_simple() -> None:
         vendor.nested.Empty.255.255 new_empty_implicit
         vendor.nested.Empty.255.255 new_empty_explicit
         vendor.nested.Empty.255.254 old_empty
-        ---#---#---#---#---#---#---#---#---
+        -----------------------------------
         Constants.5.0 constants      # RELATIVE REFERENCE
         vendor.nested.Abc.1.2 abc
         ''')

pydsdl/grammar.parsimonious

@@ -4,6 +4,8 @@ comment     = ~r"#[^\r\n]*"
 end_of_line = ~r"\r?\n"                 # Unix/Windows
 _           = ~r"[ \t]+"                # Whitespace
 
+identifier = ~r"[a-zA-Z_][a-zA-Z0-9_]*"
+
 # ==================================================== Statements ====================================================
 
 statement = statement_directive
@@ -18,15 +20,13 @@ statement_constant      = type _ identifier _? "=" _? expression
 statement_field         = type _ identifier
 statement_padding_field = type_void ""  # The trailing empty symbol is to prevent the node from being optimized away.
 
-statement_service_response_marker = "---"  # Separates request/response, specifies that the definition is a service.
+statement_service_response_marker = ~r"---+"  # Separates request/response, specifies that the definition is a service.
 
 statement_directive = statement_directive_with_expression
                     / statement_directive_without_expression
 statement_directive_with_expression    = "@" identifier _ expression  # The expression type must match the directive.
 statement_directive_without_expression = "@" identifier
 
-identifier = ~r"[a-zA-Z_][a-zA-Z0-9_]*"
-
 # ==================================================== Data types ====================================================
 
 type = type_array