Numbers

wellformed provides specialized builders for different numeric types, each with appropriate constraints.

NumberBuilder

w.number() creates a floating-point number schema.

w.number()                     // Any number
w.number().min(0)              // >= 0
w.number().max(100)            // <= 100
w.number().range(0, 100)       // 0 <= n <= 100
w.number().nonNegative()       // >= 0 (predicate-based)
w.number().positive()          // > 0
w.number().percentage()        // 0-100 range
w.number().percentage({ format: "decimal" })     // 0-1 range
w.number().percentage({ allowOver100: true })     // Uncapped
w.number().lte(999999)         // Less than or equal
w.number().gte(0.01)           // Greater than or equal
w.number().default(0)          // Default value transform

IntegerBuilder

w.integer() validates that the value is a whole number.

w.integer()                    // Any integer
w.integer().min(0).max(150)    // Range constraint
w.integer().nonNegative()      // >= 0
w.integer().positive()         // > 0
w.integer().taxYear()          // Valid tax year (2020-2100)
w.integer().taxYear({ min: 2023, max: 2025 }) // Custom range
w.integer().default(0)         // Default value transform

Specific Integer Types

For interop with the Rust crate, wellformed supports fixed-width integer types:

w.int32()          // Signed 32-bit: -2,147,483,648 to 2,147,483,647
w.int64()          // Signed 64-bit (limited to JS safe integer range)
w.uint32()         // Unsigned 32-bit: 0 to 4,294,967,295
w.uint64()         // Unsigned 64-bit (limited to JS safe integer range)

Each supports .min(), .max(), .range(), and .default():

w.int32().min(0).max(1000)
w.uint32().range(1, 100)

The validator automatically enforces the type's range even without explicit constraints.

MoneyBuilder

w.money() represents monetary amounts as numbers with optional scale.

w.money()                      // Money amount
w.money().nonNegative()        // No negative amounts
w.money().positive()           // Must be > 0
w.money().range(0, 1000000)    // Amount range
w.money().scale(2)             // 2 decimal places (default)
w.money().default(0)           // Default value

CurrencyBuilder

w.currency() adds ISO 4217 currency code support:

w.currency()                   // Any currency
w.currency().code("USD")       // US Dollar
w.currency().code("JPY").scale(0) // Yen (0 decimal places)
w.currency().code("BHD").scale(3) // Bahraini Dinar (3 decimal places)
w.currency().nonNegative()
w.currency().positive()
w.currency().range(0, 1000000)

DecimalBuilder

w.decimal() provides exact decimal representation with configurable precision and scale:

w.decimal()                        // Any decimal
w.decimal().precision(10).scale(2) // Up to 10 digits, 2 decimal places
w.decimal().nonNegative()
w.decimal().range(0, 999.99)

PercentageBuilder

w.percentage() validates percentage values:

w.percentage()                 // Decimal format (0-1), default
w.percentage().whole()         // Whole number format (0-100)
w.percentage().decimal()       // Decimal format (0-1)
w.percentage().allowOver100()  // Allow values > 100%
w.percentage().scale(4)        // 4 decimal places
w.percentage().default(0)

DateBuilder

w.date() validates date values (represented as strings):

w.date()                               // Any valid date
w.date().format("MM/DD/YYYY")          // Expected format
w.date().inRange({ minYear: 2020, maxYear: 2030 })
w.date().inRange({ min: "2024-01-01", max: "2024-12-31" })
w.date().before("2025-01-01")
w.date().after("2020-01-01", { allowEqual: true })
w.date().default("2024-01-01")

BooleanBuilder

w.boolean() validates boolean values:

w.boolean()  // true or false

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