Bool

The bool type — true/false values.

The bool type validates a boolean value. In data it is written compactly as T/F or verbosely as true/false.

For the boolean value syntax, see Booleans.

TypeDef

A bool MemberDef accepts only the options below. Any other key is invalid.

Option	Type	Description
type	string	The type name bool. First positional value.
default	bool	Value used when the member is omitted. Second positional value.
optional	bool	If true, the member may be omitted. Shorthand: ? suffix on the key.
null	bool	If true, the member may be null. Shorthand: * suffix on the key.

Examples

active: bool
---
~ T        # ✓ true
~ false    # ✓
~ yes      # ✗ not-a-bool

Optional with a default:

verified?: { bool, T }    # optional; defaults to true when omitted
---
~ {}        # ✓ verified resolves to T
~ F         # ✓ verified is F

Nullable:

flag*: bool               # nullable (value may be N)
---
~ N         # ✓ null
~ T         # ✓

Optional, nullable & defaults

Input	Result
T/true/F/false	the boolean
any other token	not-a-bool error
N, key nullable (*)	null
N, not nullable	null-not-allowed error
omitted, default set	the default
omitted, optional (?), no default	absent
omitted, required	value-required error

Use the * suffix for nullability. The keyed null: option is part of the TypeDef but is not currently honored — see Implementation status.

Implementation status (beta)

• Keyed optional: works; keyed null: is not yet honored — use the * suffix.

See Also

• Booleans (value syntax)

• TypeDef · MemberDef