Overview of Flagsets¶

A flagset is a nominal set of named bit masks:

::access FLAGSET BITS(8) [read, write, execute = 4]
{
  ::read_write STATIC access := read #|| write;
}

VAR flags access := access::read;
flags #||= access::write;

ASSERT(flags.read);
ASSERT(flags.write);
ASSERT(flags == access::read_write);

Implicit entries receive available single-bit masks. An explicit = value fixes a mask. BITS(N) fixes the stored and serialized width.

Membership and combination¶

flags.name tests whether the named mask is present. The bitwise family combines, intersects, inverts, and otherwise transforms flagset values while preserving the nominal flagset type:

VAR readable access := flags #&& access::read;
VAR without_write access := flags #&& access::write #!!;

Explicit casts convert between a flagset and a compatible unsigned integer representation when the program needs the raw mask.

Flagsets provide .SERIALIZE and .DESERIALIZE using the width declared by BITS(N).

Wide masks¶

Flagsets can span more than one machine word:

::wide_flags FLAGSET BITS(128) [low = 1, high = BIT 100];

Mask allocation, membership, and serialization retain the full declared width.

Reference¶

See the Flagsets Reference for the complete language rules, constraints, and technical edge cases.