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# -*- mode: perl; -*-
use strict;
use Scalar::Util qw< refaddr >;
my ($x, $y);
note("as_float() as a class method");
$x = Math::BigRat -> as_float("Inf");
subtest '$x = Math::BigRat -> as_float("Inf");' => sub {
plan tests => 2;
is(ref($x), 'Math::BigFloat', '$x is a Math::BigFloat');
cmp_ok($x, "==", "Inf", '$x == Inf');
};
$x = Math::BigRat -> as_float("-Inf");
subtest '$x = Math::BigRat -> as_float("-Inf");' => sub {
plan tests => 2;
is(ref($x), 'Math::BigFloat', '$x is a Math::BigFloat');
cmp_ok($x, "==", "-Inf", '$x == -Inf');
};
$x = Math::BigRat -> as_float("NaN");
subtest '$x = Math::BigRat -> as_float("NaN");' => sub {
plan tests => 2;
is(ref($x), 'Math::BigFloat', '$x is a Math::BigFloat');
is($x, "NaN", '$x is NaN');
};
$x = Math::BigRat -> as_float("2");
subtest '$x = Math::BigRat -> as_float("2");' => sub {
plan tests => 2;
is(ref($x), 'Math::BigFloat', '$x is a Math::BigFloat');
cmp_ok($x, "==", 2, '$x == 2');
};
$x = Math::BigRat -> as_float("2.5");
subtest '$x = Math::BigRat -> as_float("2.5");' => sub {
plan tests => 2;
is(ref($x), 'Math::BigFloat', '$x is a Math::BigFloat');
cmp_ok($x, "==", 2.5, '$x == 2.5');
};
note("as_float() as an instance method");
$x = Math::BigRat -> new("Inf"); $y = $x -> as_float();
subtest '$x = Math::BigRat -> new("Inf"); $y = $x -> as_float();' => sub {
plan tests => 4;
is(ref($x), 'Math::BigRat', '$x is a Math::BigRat');
is(ref($y), 'Math::BigFloat', '$y is a Math::BigFloat');
cmp_ok($y, "==", "Inf", '$y == Inf');
isnt(refaddr($x), refaddr($y), '$x and $y are different objects');
};
$x = Math::BigRat -> new("-Inf"); $y = $x -> as_float();
subtest '$x = Math::BigRat -> new("-Inf"); $y = $x -> as_float();' => sub {
plan tests => 4;
is(ref($x), 'Math::BigRat', '$x is a Math::BigRat');
is(ref($y), 'Math::BigFloat', '$y is a Math::BigFloat');
cmp_ok($y, "==", "-Inf", '$y == -Inf');
isnt(refaddr($x), refaddr($y), '$x and $y are different objects');
};
$x = Math::BigRat -> new("NaN"); $y = $x -> as_float();
subtest '$x = Math::BigRat -> new("NaN"); $y = $x -> as_float();' => sub {
plan tests => 4;
is(ref($x), 'Math::BigRat', '$x is a Math::BigRat');
is(ref($y), 'Math::BigFloat', '$y is a Math::BigFloat');
is($y, "NaN", '$y is NaN');
isnt(refaddr($x), refaddr($y), '$x and $y are different objects');
};
$x = Math::BigRat -> new("2"); $y = $x -> as_float();
subtest '$x = Math::BigRat -> new("2"); $y = $x -> as_float();' => sub {
plan tests => 4;
is(ref($x), 'Math::BigRat', '$x is a Math::BigRat');
is(ref($y), 'Math::BigFloat', '$y is a Math::BigFloat');
cmp_ok($y, "==", 2, '$y == 2');
isnt(refaddr($x), refaddr($y), '$x and $y are different objects');
};
$x = Math::BigRat -> new("2.5"); $y = $x -> as_float();
subtest '$x = Math::BigRat -> new("2.5"); $y = $x -> as_float();' => sub {
plan tests => 4;
is(ref($x), 'Math::BigRat', '$x is a Math::BigRat');
is(ref($y), 'Math::BigFloat', '$y is a Math::BigFloat');
cmp_ok($y, "==", 2.5, '$y == 2.5');
isnt(refaddr($x), refaddr($y), '$x and $y are different objects');
};
note("as_float() returns a Math::BigFloat regardless of upgrading/downgrading");
Math::BigInt -> upgrade("Math::BigRat");
Math::BigFloat -> downgrade("Math::BigInt");
Math::BigFloat -> upgrade("Math::BigRat");
$x = Math::BigRat -> new("3");
$y = $x -> as_float();
subtest '$x = Math::BigRat -> new("3"); $y = $x -> as_float();' => sub {
plan tests => 2;
is(ref($y), 'Math::BigFloat', 'class of $y');
cmp_ok($y -> numify(), "==", 3, 'value of $y');
};
$y = Math::BigRat -> as_float("3");
subtest '$y = Math::BigRat -> as_float("3");' => sub {
plan tests => 2;
is(ref($y), 'Math::BigFloat', 'class of $y');
cmp_ok($y -> numify(), "==", 3, 'value of $y');
};
$y = Math::BigRat -> as_float("3.5");
subtest 'Math::BigRat -> as_float("3.5");' => sub {
plan tests => 2;
is(ref($y), 'Math::BigFloat', 'class of $y');
cmp_ok($y -> numify(), "==", 3.5, 'value of $y');
};
Math::BigRat -> downgrade("Math::BigFloat");
$y = Math::BigRat -> as_float("3/2");
subtest 'Math::BigRat -> as_float("3/2");' => sub {
plan tests => 2;
is(ref($y), 'Math::BigFloat', 'class of $y');
cmp_ok($y -> numify(), "==", 1.5, 'value of $y');
};
note("as_float() preserves all instance variables");
Math::BigInt -> upgrade(undef);
Math::BigFloat -> downgrade(undef);
Math::BigFloat -> upgrade(undef);
$x = Math::BigRat -> new("3");
$x -> accuracy(2);
$y = $x -> as_float();
subtest '$x = Math::BigRat -> new("3"); $x -> accuracy(2); $y = $x -> as_float()'
=> sub {
plan tests => 4;
is($x -> accuracy(), 2, 'accuracy of $x');
is($x -> precision(), undef, 'precision of $x');
is($y -> accuracy(), $x -> accuracy(), 'accuracy of $y');
is($y -> precision(), $x -> precision(), 'precision of $y');
};
$x -> precision(2);
$y = $x -> as_float();
subtest '$x = Math::BigRat -> new("3"); $x -> precision(2); $y = $x -> as_float()'
=> sub {
plan tests => 4;
is($x -> accuracy(), undef, 'accuracy of $x');
is($x -> precision(), 2, 'precision of $x');
is($y -> accuracy(), $x -> accuracy(), 'accuracy of $y');
is($y -> precision(), $x -> precision(), 'precision of $y');
};
done_testing();