Cast is a Go library that provides easy and safe conversion (casting) between different types in Go programs. Especially when dealing with interface{} or dynamic/reflect-heavy code, it becomes cumbersome to assert types or convert values reliably; cast addresses that by offering a suite of functions to convert from any input to the target type with predictable behaviour. Rather than relying purely on raw type assertions, it offers ToInt, ToString, ToBool, ToTime, etc., and their “error-returning” counterparts like ToIntE. It is particularly useful when dealing with data from YAML, TOML, JSON or other formats where the type can be uncertain. The design choice is to avoid guessing about conversions: e.g., only a string strictly representing an integer can convert to int. The library is mature, tested, and widely used—thus ideal for projects that must handle dynamic input gracefully.
Features
- Functions like ToInt, ToFloat64, ToString to convert arbitrary values
- Error-returning variants (e.g., ToIntE) to detect failed conversions
- Support for slices (e.g., ToStringSlice, ToFloat64Slice) and maps (ToStringMap)
- Strict conversion semantics: only obvious conversions allowed
- Works well with dynamic data sources (JSON/YAML/TOML) where types are uncertain
- Generics and type-alias support in recent versions to streamline usage