Decimal

The decimal type — fixed-precision decimal numbers.

The decimal type validates an exact, fixed-precision decimal — for money and other values where binary floating point would lose accuracy. In data it is written with an m suffix: 123.45m.

For the literal syntax, see Decimal values.

TypeDef

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

Option	Type	Description
type	string	The type name decimal. First positional value.
default	decimal	Value used when the member is omitted. Second positional value.
choices	array of decimal	Restricts the value to a fixed set.
precision	int	Maximum total number of significant digits.
scale	int	Exact number of digits after the decimal point.
min	decimal	Minimum allowed value (inclusive).
max	decimal	Maximum allowed value (inclusive).
multipleOf	decimal	The value must be an exact multiple of this.
optional	bool	If true, the member may be omitted. Shorthand: ? suffix.
null	bool	If true, the member may be null. Shorthand: * suffix.

Precision & scale

precision and scale together give SQL-style DECIMAL(precision, scale) validation:

• scale — the number of fractional digits MUST equal scale.

• precision — the total significant digits MUST NOT exceed precision.

price: { decimal, precision: 5, scale: 2 }
---
~ 123.45m    # ✓  (5 digits, 2 after the point)

rate: { decimal, scale: 2 }
---
~ 1.5m       # ✗ invalid-scale  (1 fractional digit, scale requires 2)

With neither precision nor scale, a decimal is compared by its exact value.

Optional, nullable & defaults

Resolution follows the common rules:

amount?*: decimal
---
~ {}      # ✓ omitted → absent
~ N       # ✓ null
~ 9.99m   # ✓

Implementation status (beta)

• Keyed null: is not yet honored — use the * suffix.

See Also

• Decimal values

• Numeric Types · BigInt

• TypeDef · MemberDef