gostructor

Supported field types

• int, int8, int16, int32, int64
• uint, uint8, uint16, uint32, uint64
• float32, float64
• string
• bool
• time.Duration, filled from a Go duration string like "1h30m" (numeric sources are read as nanoseconds, matching encoding/json).
• any named scalar type (type Level int, type Env string, …) — the value is converted to the field’s underlying kind and keeps the named type.
• any type implementing encoding.TextUnmarshaler (time.Time, net.IP, your own enums), filled by handing it the string form.
• pointers to any of the above (*int, *time.Time, …): the value is allocated and set. Multi-level pointers (**T) are not supported.
• slices and fixed-size arrays of any supported element type, including nested ones — []int32, [3]string, [][]int, []time.Duration. For an array the source must have exactly the array’s length.
• map[K]V and []Struct / map[string]Struct, when the source is structured data (JSON, YAML, TOML, HOCON) and the tag addresses a whole nested object rather than one leaf value. Struct elements are filled by matching each exported field to an object key by name, case-insensitively. The env, default, ini, and vault sources encode values as a flat string and so can only populate slices, not maps or struct elements.

Numeric conversions are exact: a fractional float into an integer field (3.9 → int), a value that overflows the field’s width (300 → int8), a negative number into an unsigned field, and non-finite floats are all hard errors — never silent truncation or wraparound. A conversion failure is reported as a *ConvertError (see limitations.md).

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