[asl] Some minor lexer/parser tidying

Partly from suggestions by @acjf3 and @ldesnogu

Author: hrutvik

asllib/Lexer.mll

@@ -386,9 +386,9 @@ let mask = (bit | 'x' | '(' bit+ ')')*
 let identifier = alpha_ (alpha_|digit)*
 
 let forbidden_hex_first = '0' 'x' [^'a'-'f' 'A'-'F' '0'-'9']
-let forbidden_hex_remaining = '0' 'x' hex_digit hex_digit_* ['g'-'z' 'G'-'Z']
+let forbidden_hex_remaining = hex_lit ['g'-'z' 'G'-'Z']
 let forbidden_real_first = int_lit '.' [^'0'-'9' '.']
-let forbidden_real_remaining = int_lit '.' digit digit_* alpha
+let forbidden_real_remaining = int_lit '.' int_lit alpha
 
 (*
    Lexing of string literals

asllib/Parser.mly

@@ -522,8 +522,6 @@ let global_keyword ==
   | global_keyword_non_config
   | CONFIG; { GDK_Config }
 
-let pass == { S_Pass }
-let assign(x, y) == ~=x ; EQ ; ~=y ; < S_Assign >
 let direction := | TO; { AST.Up } | DOWNTO; { AST.Down }
 
 let case_alt :=
@@ -562,8 +560,8 @@ let stmt :=
       | TRY; s=stmt_list; CATCH; c=list1(catcher); o=otherwise_opt; < S_Try >
     )
     | terminated_by(SEMI_COLON,
-      | PASS; pass
-      | RETURN; ~=option(expr);                             < S_Return >
+      | PASS;                                                { S_Pass }
+      | RETURN; ~=option(expr);                              < S_Return >
       | ~=call;                                              < s_call >
       | ASSERT; e=expr;                                      < S_Assert >
       | ~=local_decl_keyword; ~=decl_item; ~=ty_opt; EQ; ~=some(expr); < S_Decl   >
@@ -593,7 +591,7 @@ let stmt_list := ~ = list1(stmt) ; <stmt_from_list>
 let s_else :=
   annotated (
     | ELSIF; e=expr; THEN; s1=stmt_list; s2=s_else; <S_Cond>
-    | pass
+    | { S_Pass }
   )
   | ELSE; stmt_list
 

asllib/doc/LexicalStructure.tex

@@ -150,9 +150,7 @@ \section{Integer Literals\label{sec:Integer Literals}}
 $\REhexlit$ &$\triangleq$& \texttt{"0x"} (\REdigit\ \texttt{|} \REhexletter) \\
             &            & $\wrappedline$ (\Underscore\ \texttt{|} \REdigit\ \texttt{|} \REhexletter)* \\
 $\REforbiddenhexfirst$ &$\triangleq$& \texttt{"0x"} ((\REchar\ \regexminus{} \REdigit) \regexminus{} \REhexletter) \\
-$\REforbiddenhexremaining$ &$\triangleq$& \texttt{"0x"} (\REdigit\ \texttt{|} \REhexletter)  \\
-                           &            & $\wrappedline$ (\Underscore\ \texttt{|} \REdigit\ \texttt{|} \REhexletter)*  \\
-                           &            & $\wrappedline$ (\REletter{} \regexminus{} \REhexletter) \\
+$\REforbiddenhexremaining$ &$\triangleq$& $\REhexlit$ (\REletter{} \regexminus{} \REhexletter) \\
 \end{tabular}
 \end{center}
 
@@ -172,12 +170,9 @@ \section{Rational Number Literals\label{sec:Rational Number Literals}}
 This is formalized by the following lexical regular expression:
 \begin{center}
 \begin{tabular}{rcl}
-$\REreallit$  &$\triangleq$ & \texttt{\REdigit\ (\Underscore\ | \REdigit)* "." \REdigit} \\
-              &             & $\wrappedline$ \texttt{(\Underscore\ | \REdigit)*} \\
-$\REforbiddenrealfirst$ &$\triangleq$ & \texttt{\REdigit\ (\Underscore\ | \REdigit)* "."} \\
-              &             & $\wrappedline$ \texttt{ (\REchar\ \regexminus{} \anycharacter{\texttt{0123456789.}})} \\
-$\REforbiddenrealremaining$ &$\triangleq$& \texttt{\REdigit\ (\Underscore\ | \REdigit)* "." \REdigit} \\
-              &            & $\wrappedline$ \texttt{(\Underscore\ | \REdigit)* \REletter{}} \\
+$\REreallit$  &$\triangleq$ & $\REintlit$ \texttt{"."} $\REintlit$ \\
+$\REforbiddenrealfirst$ &$\triangleq$ & $\REintlit$ \texttt{ (\REchar\ \regexminus{} \anycharacter{\texttt{0123456789.}})} \\
+$\REforbiddenrealremaining$ &$\triangleq$& $\REintlit$ \texttt{"."} $\REintlit$ \REletter{} \\
 \end{tabular}
 \end{center}