Re: Grammar-problems with pl/pgsql in gram.y - Mailing list pgsql-hackers

Am Mittwoch, 16. Mai 2001 16:10 schrieb Jan Wieck:
>     Here it is. stmt_else is defined as type <stmts>, not <stmt>.
>     The PLpgSQL_stmt_if struct has  a  condition  query  and  two
>     statement lists (type <stmts>). You're trying to put a single
>     statement into the else part instead of a list of statements.
Thank you for the hint! That was it.

>     Maybe   it'll   work   if   you   surround  it  with  another
>     PLpgSQL_stmts struct where your new  PLpgSQL_stmt_if  is  the
>     only  statement  in it's list.  Since I have some bigger work
>     outstanding for PL/pgSQL, send the resulting  patch  (if  you
>     get it to work) directly to me.
The patch follows this message. May you tell me what kind of work it is, 
cause I'm so curous :-). By the way, the next thing I try is a
EXCEPTION WHEN OTHER-clause, like in Oracle. Let's look if I'm successful.

Ciao, Klaus

----------------------------------------------------------------------------

diff -Naurb src/gram.y src.elsif/gram.y
--- src/gram.y    Wed May 16 18:00:53 2001
+++ src.elsif/gram.y    Wed May 16 17:39:19 2001
@@ -147,6 +147,7 @@%token    K_DIAGNOSTICS%token    K_DOTDOT%token    K_ELSE
+%token    K_ELSIF%token    K_END%token    K_EXCEPTION%token    K_EXECUTE
@@ -544,6 +545,7 @@                                new->stmts[0] = (struct PLpgSQL_stmt *)$1;
    $$ = new;
 
+                        }                ;
@@ -721,8 +723,53 @@                            memset(new, 0, sizeof(PLpgSQL_stmts));                            $$ =
new;                   }
 
+                | K_ELSIF lno expr_until_then proc_sect stmt_else
+                    {
+                      /*
+                       * Translate the structure:       into:
+                       *
+                       * IF c1 THEN                       IF c1 THEN         
+                       *     ...                           ...                 
+                       * ELSIF c2 THEN                   ELSE 
+                       *                                   IF c2 THEN    
+                       *     ...                               ...                 
+                       * ELSE                               ELSE                 
+                       *     ...                               ...                 
+                       * END IF                               END IF             
+                       *                               END IF
+                       * 
+                       */
+
+                        PLpgSQL_stmts    *new;
+                        PLpgSQL_stmt_if *new_if;
+
+                        /* first create a new if-statement */
+                        new_if = malloc(sizeof(PLpgSQL_stmt_if));
+                        memset(new_if, 0, sizeof(PLpgSQL_stmt_if));
+
+                        new_if->cmd_type    = PLPGSQL_STMT_IF;
+                        new_if->lineno        = $2;
+                        new_if->cond        = $3;
+                        new_if->true_body    = $4;
+                        new_if->false_body    = $5;
+                        
+                        /* this is a 'container' for the if-statement */
+                        new = malloc(sizeof(PLpgSQL_stmts));
+                        memset(new, 0, sizeof(PLpgSQL_stmts));
+                        
+                        new->stmts_alloc = 64;
+                        new->stmts_used     = 1;
+                        new->stmts = malloc(sizeof(PLpgSQL_stmt *) * new->stmts_alloc);
+                        new->stmts[0] = (struct PLpgSQL_stmt *)new_if;
+
+                        $$ = new;
+                        
+                    }
+                | K_ELSE proc_sect
-                    { $$ = $2; }
+                    {
+                        $$ = $2;                
+                    }                ;stmt_loop        : opt_label K_LOOP lno loop_body
@@ -1271,7 +1318,6 @@                break;        }    }
-    expr = malloc(sizeof(PLpgSQL_expr) + sizeof(int) * nparams - sizeof(int));    expr->dtype            =
PLPGSQL_DTYPE_EXPR;   expr->query            = strdup(plpgsql_dstring_get(&ds));
 
diff -Naurb src/scan.l src.elsif/scan.l
--- src/scan.l    Wed May 16 18:01:36 2001
+++ src.elsif/scan.l    Tue May 15 12:49:43 2001
@@ -99,6 +99,7 @@default            { return K_DEFAULT;            }diagnostics        { return K_DIAGNOSTICS;
}else           { return K_ELSE;            }
 
+elsif           { return K_ELSIF;           }end                { return K_END;                }exception        {
returnK_EXCEPTION;        }execute            { return K_EXECUTE;            }