ΜOpal: Unterschied zwischen den Versionen
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</pre> | </pre> | ||
| − | [[EBNF]]: | + | [[Wikipedia:EBNF|EBNF]]: |
<pre> | <pre> | ||
Prog -> Def Def* "#" | Prog -> Def Def* "#" | ||
Version vom 13. Februar 2006, 20:47 Uhr
Eine simple Programmiersprache zu der in der Lehrveranstaltung PSS ein Compiler geschrieben wird.
Beispielprogramm:
DEF fac(X:nat):nat ==
IF eq(X,0)
THEN 1
ELSE mul(X, fac(sub(X, 1)))
FI
DEF MAIN:nat ==
fac(8)
EBNF:
Prog -> Def Def* "#"
Def -> "DEF" Lhs "==" Expr
Lhs -> "MAIN" ":" Type
| "id" "(" [ "id" ":" Type ( "," "id" ":" Type )* ] ")" ":" Type
Type -> "nat"
| "bool"
Expr -> "number"
| "true"
| "false"
| "id" [ "(" [ Expr ( "," Expr )* ] ")" ]
| "IF" Expr "THEN" Expr [ "ELSE" Expr ] "FI"