Booleans

Boolean values — true and false, in compact and verbose forms.

A boolean is a logical value, either true or false. Booleans are scalar values used for flags, binary states, and conditions.

Each value has a compact and a verbose form, letting you trade brevity for explicitness.

Syntax

boolean        = compactBoolean | verboseBoolean
compactBoolean = "T" | "F"
verboseBoolean = "true" | "false"

Structural elements

Token	Name	Description
T	Compact true	true in compact form
F	Compact false	false in compact form
true	Verbose true	the verbose true keyword
false	Verbose false	the verbose false keyword

Valid forms

The compact and verbose forms are equivalent; the compact form is recommended for terse data.

---
T, F, true, false

Not a boolean

Boolean keywords are case-sensitive and spelled exactly. Any other token is not an error — it is parsed as a different value type, so it is not a boolean:

t                    # open string "t", not true
TRUE                 # open string "TRUE", not true
True                 # open string "True", not true
1                    # the number 1, not true
0                    # the number 0, not false

Under a bool schema, a non-boolean value fails validation with expected-boolean. Without a schema, the values above are simply kept as their parsed type (string or number).

See Also

• Value Representations — all value types

• Nulls — the absence of a value

• Bool — the boolean schema type