oceani: remove "and then" and "or else"

I can't think of any reason that "and" and "or" shouldn't be
short-circuit operators, so change them to do what "and then" and "or
else" currently do, and discard the latter.

Signed-off-by: NeilBrown <neil@brown.name>

diff --git a/csrc/oceani-tests.mdc b/csrc/oceani-tests.mdc
index 6759c542d6d7dd72093a99babcbcd02fafb26173..0feb0d20ba0b86f17869b47931e998705a23a0d3 100644 (file)
--- a/csrc/oceani-tests.mdc
+++ b/csrc/oceani-tests.mdc
@@ -274,12 +274,12 @@ Now we need to test if/else and some different loops
                print "error is ", target - guess * guess
 
                for j:=0; then j = j+3 ; while j < 10:
-                       if j != 0 and then 20 / j > 3:
+                       if j != 0 and 20 / j > 3:
                                print "20 /", j," =", 20 / j
                        else
                                print "I won't calculate 20 /", j
                pi ::= 3.1415926535897
-               if 355/113 == pi or else +(pi - 355/113) < 0.001:
+               if 355/113 == pi or +(pi - 355/113) < 0.001:
                        print "Close enough"
                print "lower" if 355/113 < pi else "higher"
                print "higher" if 355/113 > pi else "lower"
@@ -781,7 +781,7 @@ A simple linked list example
 
        func insert(list:@linkage; new:string)
                p:=list
-               while ?p.next and then p.next.this < new:
+               while ?p.next and p.next.this < new:
                        p = p.next.list
                t:@node = @new()
                t.list.next = p.next

diff --git a/csrc/oceani.mdc b/csrc/oceani.mdc
index 910d0953572c639ed76f985e764c0402eec8a482..d40a5488f4de9d0755896493b15ba6e05bb5804b 100644 (file)
--- a/csrc/oceani.mdc
+++ b/csrc/oceani.mdc
@@ -37,9 +37,9 @@ boolean operators.
 
 Some operators that have only recently been added, and so have not
 generated all that much experience yet are "and then" and "or else" as
-short-circuit Boolean operators, and the "if ... else" trinary
-operator which can select between two expressions based on a third
-(which appears syntactically in the middle).
+short-circuit Boolean operators (which have since been remove), and the
+"if ...  else" trinary operator which can select between two expressions
+based on a third (which appears syntactically in the middle).
 
 The "func" clause currently only allows a "main" function to be
 declared.  That will be extended when proper function support is added.
@@ -3932,15 +3932,12 @@ lists.  In that case a separate function is used to print them.
 ### Expressions: Boolean
 
 The next class of expressions to use the `binode` will be Boolean
-expressions.  "`and then`" and "`or else`" are similar to `and` and `or`
-have same corresponding precendence.  The difference is that they don't
+expressions.  `and` and `or` are short-circuit operators that don't
 evaluate the second expression if not necessary.
 
 ###### Binode types
        And,
-       AndThen,
        Or,
-       OrElse,
        Not,
 
 ###### declare terminals
@@ -3956,14 +3953,6 @@ evaluate the second expression if not necessary.
                b->right = $<3;
                $0 = b;
        } }$
-       | Expression or else Expression ${ {
-               struct binode *b = new(binode);
-               b->op = OrElse;
-               b->left = $<1;
-               b->right = $<4;
-               $0 = b;
-       } }$
-
        | Expression and Expression ${ {
                struct binode *b = new(binode);
                b->op = And;
@@ -3971,14 +3960,6 @@ evaluate the second expression if not necessary.
                b->right = $<3;
                $0 = b;
        } }$
-       | Expression and then Expression ${ {
-               struct binode *b = new(binode);
-               b->op = AndThen;
-               b->left = $<1;
-               b->right = $<4;
-               $0 = b;
-       } }$
-
        | not Expression ${ {
                struct binode *b = new(binode);
                b->op = Not;
@@ -3994,13 +3975,6 @@ evaluate the second expression if not necessary.
                print_exec(b->right, -1, bracket);
                if (bracket) printf(")");
                break;
-       case AndThen:
-               if (bracket) printf("(");
-               print_exec(b->left, -1, bracket);
-               printf(" and then ");
-               print_exec(b->right, -1, bracket);
-               if (bracket) printf(")");
-               break;
        case Or:
                if (bracket) printf("(");
                print_exec(b->left, -1, bracket);
@@ -4008,13 +3982,6 @@ evaluate the second expression if not necessary.
                print_exec(b->right, -1, bracket);
                if (bracket) printf(")");
                break;
-       case OrElse:
-               if (bracket) printf("(");
-               print_exec(b->left, -1, bracket);
-               printf(" or else ");
-               print_exec(b->right, -1, bracket);
-               if (bracket) printf(")");
-               break;
        case Not:
                if (bracket) printf("(");
                printf("not ");
@@ -4024,9 +3991,7 @@ evaluate the second expression if not necessary.
 
 ###### propagate binode cases
        case And:
-       case AndThen:
        case Or:
-       case OrElse:
        case Not:
                /* both must be Tbool, result is Tbool */
                propagate_types(b->left, c, perr, Tbool, 0);
@@ -4039,21 +4004,11 @@ evaluate the second expression if not necessary.
 
 ###### interp binode cases
        case And:
-               rv = interp_exec(c, b->left, &rvtype);
-               right = interp_exec(c, b->right, &rtype);
-               rv.bool = rv.bool && right.bool;
-               break;
-       case AndThen:
                rv = interp_exec(c, b->left, &rvtype);
                if (rv.bool)
                        rv = interp_exec(c, b->right, NULL);
                break;
        case Or:
-               rv = interp_exec(c, b->left, &rvtype);
-               right = interp_exec(c, b->right, &rtype);
-               rv.bool = rv.bool || right.bool;
-               break;
-       case OrElse:
                rv = interp_exec(c, b->left, &rvtype);
                if (!rv.bool)
                        rv = interp_exec(c, b->right, NULL);
@@ -5998,7 +5953,7 @@ things which will likely grow as the languages grows.
                a : number
                a = A;
                b:number = B
-               if a > 0 and then b > 0:
+               if a > 0 and b > 0:
                        while a != b:
                                if a < b:
                                        b = b - a