Work on exception handling, especially around ratio arithmetic

Much simplified but will break things!
This commit is contained in:
Simon Brooke 2021-07-25 17:02:28 +01:00
parent d2101dbd47
commit 70d176982b
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GPG key ID: A7A4F18D1D4DF987
14 changed files with 298 additions and 258 deletions

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@ -43,52 +43,52 @@ int64_t least_common_multiple( int64_t m, int64_t n ) {
return m / greatest_common_divisor( m, n ) * n;
}
/**
* return a cons_pointer indicating a number which is of the
* same value as the ratio indicated by `arg`, but which may
* be in a simplified representation.
* @exception If `arg` isn't a ratio, will return an exception.
*/
struct cons_pointer simplify_ratio( struct cons_pointer frame_pointer,
struct cons_pointer arg ) {
struct cons_pointer result = arg;
struct cons_pointer simplify_ratio( struct cons_pointer pointer) {
struct cons_pointer result = pointer;
struct cons_space_object cell = pointer2cell(pointer);
struct cons_space_object dividend = pointer2cell(cell.payload.ratio.dividend);
struct cons_space_object divisor = pointer2cell(cell.payload.ratio.divisor);
if ( ratiop( arg ) ) {
int64_t ddrv =
pointer2cell( pointer2cell( arg ).payload.ratio.dividend ).
payload.integer.value, drrv =
pointer2cell( pointer2cell( arg ).payload.ratio.divisor ).
payload.integer.value, gcd = greatest_common_divisor( ddrv, drrv );
if (divisor.payload.integer.value == 1)
{
result = pointer2cell(pointer).payload.ratio.dividend;
}
else
{
if (ratiop(pointer))
{
int64_t ddrv = dividend.payload.integer.value,
drrv = divisor.payload.integer.value,
gcd = greatest_common_divisor(ddrv, drrv);
if ( gcd > 1 ) {
if ( drrv / gcd == 1 ) {
result = make_integer( ddrv / gcd, NIL );
} else {
result =
make_ratio( frame_pointer, make_integer( ddrv / gcd, NIL ),
make_integer( drrv / gcd, NIL ) );
if (gcd > 1)
{
if (drrv / gcd == 1)
{
result = make_integer(ddrv / gcd, NIL);
}
else
{
result =
make_ratio(make_integer(ddrv / gcd, NIL),
make_integer(drrv / gcd, NIL));
}
}
}
} else {
result =
throw_exception( make_cons( c_string_to_lisp_string
( L"Shouldn't happen: bad arg to simplify_ratio" ),
arg ), frame_pointer );
}
return result;
}
/**
* return a cons_pointer indicating a number which is the sum of
* the ratios indicated by `arg1` and `arg2`.
* @exception will return an exception if either `arg1` or `arg2` is not a
* rational number.
*/
struct cons_pointer add_ratio_ratio( struct cons_pointer frame_pointer,
struct cons_pointer arg1,
struct cons_pointer add_ratio_ratio( struct cons_pointer arg1,
struct cons_pointer arg2 ) {
struct cons_pointer r, result;
@ -116,18 +116,17 @@ struct cons_pointer add_ratio_ratio( struct cons_pointer frame_pointer,
m1, m2 );
if ( dr1v == dr2v ) {
r = make_ratio( frame_pointer,
make_integer( dd1v + dd2v, NIL ),
r = make_ratio( make_integer( dd1v + dd2v, NIL ),
cell1.payload.ratio.divisor );
} else {
struct cons_pointer dd1vm = make_integer( dd1v * m1, NIL ),
dr1vm = make_integer( dr1v * m1, NIL ),
dd2vm = make_integer( dd2v * m2, NIL ),
dr2vm = make_integer( dr2v * m2, NIL ),
r1 = make_ratio( frame_pointer, dd1vm, dr1vm ),
r2 = make_ratio( frame_pointer, dd2vm, dr2vm );
r1 = make_ratio( dd1vm, dr1vm ),
r2 = make_ratio( dd2vm, dr2vm );
r = add_ratio_ratio( frame_pointer, r1, r2 );
r = add_ratio_ratio( r1, r2 );
/* because the references on dd1vm, dr1vm, dd2vm and dr2vm were
* never incremented except when making r1 and r2, decrementing
@ -136,7 +135,7 @@ struct cons_pointer add_ratio_ratio( struct cons_pointer frame_pointer,
dec_ref( r2 );
}
result = simplify_ratio( frame_pointer, r );
result = simplify_ratio( r );
if ( !eq( r, result ) ) {
dec_ref( r );
}
@ -146,7 +145,7 @@ struct cons_pointer add_ratio_ratio( struct cons_pointer frame_pointer,
( L"Shouldn't happen: bad arg to add_ratio_ratio" ),
make_cons( arg1,
make_cons( arg2, NIL ) ) ),
frame_pointer );
NIL );
}
debug_print( L" => ", DEBUG_ARITH );
@ -163,16 +162,16 @@ struct cons_pointer add_ratio_ratio( struct cons_pointer frame_pointer,
* `ratarg`.
* @exception if either `intarg` or `ratarg` is not of the expected type.
*/
struct cons_pointer add_integer_ratio( struct cons_pointer frame_pointer,
struct cons_pointer intarg,
struct cons_pointer add_integer_ratio( struct cons_pointer intarg,
struct cons_pointer ratarg ) {
struct cons_pointer result;
if ( integerp( intarg ) && ratiop( ratarg ) ) {
// TODO: not longer works
struct cons_pointer one = make_integer( 1, NIL ),
ratio = make_ratio( frame_pointer, intarg, one );
ratio = make_ratio( intarg, one );
result = add_ratio_ratio( frame_pointer, ratio, ratarg );
result = add_ratio_ratio( ratio, ratarg );
dec_ref( one );
dec_ref( ratio );
@ -183,7 +182,7 @@ struct cons_pointer add_integer_ratio( struct cons_pointer frame_pointer,
make_cons( intarg,
make_cons( ratarg,
NIL ) ) ),
frame_pointer );
NIL );
}
return result;
@ -195,15 +194,14 @@ struct cons_pointer add_integer_ratio( struct cons_pointer frame_pointer,
* @exception will return an exception if either `arg1` or `arg2` is not a
* rational number.
*/
struct cons_pointer divide_ratio_ratio( struct cons_pointer frame_pointer,
struct cons_pointer arg1,
struct cons_pointer divide_ratio_ratio( struct cons_pointer arg1,
struct cons_pointer arg2 ) {
struct cons_pointer i = make_ratio( frame_pointer,
pointer2cell( arg2 ).payload.
// TODO: this now has to work if `arg1` is an integer
struct cons_pointer i = make_ratio( pointer2cell( arg2 ).payload.
ratio.divisor,
pointer2cell( arg2 ).payload.
ratio.dividend ), result =
multiply_ratio_ratio( frame_pointer, arg1, i );
multiply_ratio_ratio( arg1, i );
dec_ref( i );
@ -216,9 +214,10 @@ struct cons_pointer divide_ratio_ratio( struct cons_pointer frame_pointer,
* @exception will return an exception if either `arg1` or `arg2` is not a
* rational number.
*/
struct cons_pointer multiply_ratio_ratio( struct cons_pointer frame_pointer, struct
struct cons_pointer multiply_ratio_ratio( struct
cons_pointer arg1, struct
cons_pointer arg2 ) {
// TODO: this now has to work if arg1 is an integer
struct cons_pointer result;
debug_print( L"multiply_ratio_ratio( arg1 = ", DEBUG_ARITH );
@ -241,9 +240,9 @@ struct cons_pointer multiply_ratio_ratio( struct cons_pointer frame_pointer, str
ddrv = dd1v * dd2v, drrv = dr1v * dr2v;
struct cons_pointer unsimplified =
make_ratio( frame_pointer, make_integer( ddrv, NIL ),
make_ratio( make_integer( ddrv, NIL ),
make_integer( drrv, NIL ) );
result = simplify_ratio( frame_pointer, unsimplified );
result = simplify_ratio( unsimplified );
if ( !eq( unsimplified, result ) ) {
dec_ref( unsimplified );
@ -252,7 +251,7 @@ struct cons_pointer multiply_ratio_ratio( struct cons_pointer frame_pointer, str
result =
throw_exception( c_string_to_lisp_string
( L"Shouldn't happen: bad arg to multiply_ratio_ratio" ),
frame_pointer );
NIL );
}
return result;
@ -264,15 +263,15 @@ struct cons_pointer multiply_ratio_ratio( struct cons_pointer frame_pointer, str
* `ratarg`.
* @exception if either `intarg` or `ratarg` is not of the expected type.
*/
struct cons_pointer multiply_integer_ratio( struct cons_pointer frame_pointer,
struct cons_pointer intarg,
struct cons_pointer multiply_integer_ratio( struct cons_pointer intarg,
struct cons_pointer ratarg ) {
struct cons_pointer result;
if ( integerp( intarg ) && ratiop( ratarg ) ) {
// TODO: no longer works; fix
struct cons_pointer one = make_integer( 1, NIL ),
ratio = make_ratio( frame_pointer, intarg, one );
result = multiply_ratio_ratio( frame_pointer, ratio, ratarg );
ratio = make_ratio( intarg, one );
result = multiply_ratio_ratio( ratio, ratarg );
dec_ref( one );
dec_ref( ratio );
@ -280,7 +279,7 @@ struct cons_pointer multiply_integer_ratio( struct cons_pointer frame_pointer,
result =
throw_exception( c_string_to_lisp_string
( L"Shouldn't happen: bad arg to multiply_integer_ratio" ),
frame_pointer );
NIL );
}
return result;
@ -293,11 +292,10 @@ struct cons_pointer multiply_integer_ratio( struct cons_pointer frame_pointer,
* @exception will return an exception if either `arg1` or `arg2` is not a
* rational number.
*/
struct cons_pointer subtract_ratio_ratio( struct cons_pointer frame_pointer,
struct cons_pointer arg1,
struct cons_pointer subtract_ratio_ratio( struct cons_pointer arg1,
struct cons_pointer arg2 ) {
struct cons_pointer i = negative( frame_pointer, arg2 ),
result = add_ratio_ratio( frame_pointer, arg1, i );
struct cons_pointer i = negative( arg2),
result = add_ratio_ratio( arg1, i );
dec_ref( i );
@ -311,8 +309,7 @@ struct cons_pointer subtract_ratio_ratio( struct cons_pointer frame_pointer,
* `frame_pointer`.
* @exception if either `dividend` or `divisor` is not an integer.
*/
struct cons_pointer make_ratio( struct cons_pointer frame_pointer,
struct cons_pointer dividend,
struct cons_pointer make_ratio( struct cons_pointer dividend,
struct cons_pointer divisor ) {
struct cons_pointer result;
if ( integerp( dividend ) && integerp( divisor ) ) {
@ -326,10 +323,30 @@ struct cons_pointer make_ratio( struct cons_pointer frame_pointer,
result =
throw_exception( c_string_to_lisp_string
( L"Dividend and divisor of a ratio must be integers" ),
frame_pointer );
NIL );
}
debug_dump_object( result, DEBUG_ARITH );
return result;
}
/**
* True if a and be are identical ratios, else false.
*/
bool equal_ratio_ratio(struct cons_pointer a, struct cons_pointer b)
{
bool result = false;
if (ratiop(a) && ratiop(b))
{
struct cons_space_object *cell_a = &pointer2cell(a);
struct cons_space_object *cell_b = &pointer2cell(b);
result = equal_integer_integer(cell_a->payload.ratio.dividend,
cell_b->payload.ratio.dividend) &&
equal_integer_integer(cell_a->payload.ratio.divisor,
cell_b->payload.ratio.divisor);
}
return result;
}