uniqnum

Remove subsequent duplicates by numerical equality, preserving order.

Synopsis

my @subset = uniqnum @values;
my $count  = uniqnum @values;    # scalar context — count only

What you get back

In list context, the unique numerical values in first-seen order. In scalar context, the count. undef is treated as 0 and coerced to 0 in the output (matching upstream’s numerical handling). +0.0 and -0.0 are treated as equal. Every NaN is treated as a duplicate of every other NaN, despite NaN != NaN.

Examples

my @u = uniqnum  1, 1.0, '1', 2;   # (1, 2)
my @u = uniqnum  0, -0.0;          # (0)
my $n = uniqnum  1, 2, 3, 2, 1;    # 3

Differences from upstream

Fully compatible with upstream.

See also

• uniq — string-equality deduplication.

• uniqint — integer-equality deduplication (ignores fractions).