package cty import ( "fmt" "math/big" "reflect" "golang.org/x/text/unicode/norm" "github.com/zclconf/go-cty/cty/set" ) // BoolVal returns a Value of type Number whose internal value is the given // bool. func BoolVal(v bool) Value { return Value{ ty: Bool, v: v, } } // NumberVal returns a Value of type Number whose internal value is the given // big.Float. The returned value becomes the owner of the big.Float object, // and so it's forbidden for the caller to mutate the object after it's // wrapped in this way. func NumberVal(v *big.Float) Value { return Value{ ty: Number, v: v, } } // ParseNumberVal returns a Value of type number produced by parsing the given // string as a decimal real number. To ensure that two identical strings will // always produce an equal number, always use this function to derive a number // from a string; it will ensure that the precision and rounding mode for the // internal big decimal is configured in a consistent way. // // If the given string cannot be parsed as a number, the returned error has // the message "a number is required", making it suitable to return to an // end-user to signal a type conversion error. // // If the given string contains a number that becomes a recurring fraction // when expressed in binary then it will be truncated to have a 512-bit // mantissa. Note that this is a higher precision than that of a float64, // so coverting the same decimal number first to float64 and then calling // NumberFloatVal will not produce an equal result; the conversion first // to float64 will round the mantissa to fewer than 512 bits. func ParseNumberVal(s string) (Value, error) { // Base 10, precision 512, and rounding to nearest even is the standard // way to handle numbers arriving as strings. f, _, err := big.ParseFloat(s, 10, 512, big.ToNearestEven) if err != nil { return NilVal, fmt.Errorf("a number is required") } return NumberVal(f), nil } // MustParseNumberVal is like ParseNumberVal but it will panic in case of any // error. It can be used during initialization or any other situation where // the given string is a constant or otherwise known to be correct by the // caller. func MustParseNumberVal(s string) Value { ret, err := ParseNumberVal(s) if err != nil { panic(err) } return ret } // NumberIntVal returns a Value of type Number whose internal value is equal // to the given integer. func NumberIntVal(v int64) Value { return NumberVal(new(big.Float).SetInt64(v)) } // NumberUIntVal returns a Value of type Number whose internal value is equal // to the given unsigned integer. func NumberUIntVal(v uint64) Value { return NumberVal(new(big.Float).SetUint64(v)) } // NumberFloatVal returns a Value of type Number whose internal value is // equal to the given float. func NumberFloatVal(v float64) Value { return NumberVal(new(big.Float).SetFloat64(v)) } // StringVal returns a Value of type String whose internal value is the // given string. // // Strings must be UTF-8 encoded sequences of valid unicode codepoints, and // they are NFC-normalized on entry into the world of cty values. // // If the given string is not valid UTF-8 then behavior of string operations // is undefined. func StringVal(v string) Value { return Value{ ty: String, v: NormalizeString(v), } } // NormalizeString applies the same normalization that cty applies when // constructing string values. // // A return value from this function can be meaningfully compared byte-for-byte // with a Value.AsString result. func NormalizeString(s string) string { return norm.NFC.String(s) } // ObjectVal returns a Value of an object type whose structure is defined // by the key names and value types in the given map. func ObjectVal(attrs map[string]Value) Value { attrTypes := make(map[string]Type, len(attrs)) attrVals := make(map[string]interface{}, len(attrs)) for attr, val := range attrs { attr = NormalizeString(attr) attrTypes[attr] = val.ty attrVals[attr] = val.v } return Value{ ty: Object(attrTypes), v: attrVals, } } // TupleVal returns a Value of a tuple type whose element types are // defined by the value types in the given slice. func TupleVal(elems []Value) Value { elemTypes := make([]Type, len(elems)) elemVals := make([]interface{}, len(elems)) for i, val := range elems { elemTypes[i] = val.ty elemVals[i] = val.v } return Value{ ty: Tuple(elemTypes), v: elemVals, } } // ListVal returns a Value of list type whose element type is defined by // the types of the given values, which must be homogenous. // // If the types are not all consistent (aside from elements that are of the // dynamic pseudo-type) then this function will panic. It will panic also // if the given list is empty, since then the element type cannot be inferred. // (See also ListValEmpty.) func ListVal(vals []Value) Value { if len(vals) == 0 { panic("must not call ListVal with empty slice") } elementType := DynamicPseudoType rawList := make([]interface{}, len(vals)) for i, val := range vals { if elementType == DynamicPseudoType { elementType = val.ty } else if val.ty != DynamicPseudoType && !elementType.Equals(val.ty) { panic(fmt.Errorf( "inconsistent list element types (%#v then %#v)", elementType, val.ty, )) } rawList[i] = val.v } return Value{ ty: List(elementType), v: rawList, } } // ListValEmpty returns an empty list of the given element type. func ListValEmpty(element Type) Value { return Value{ ty: List(element), v: []interface{}{}, } } // MapVal returns a Value of a map type whose element type is defined by // the types of the given values, which must be homogenous. // // If the types are not all consistent (aside from elements that are of the // dynamic pseudo-type) then this function will panic. It will panic also // if the given map is empty, since then the element type cannot be inferred. // (See also MapValEmpty.) func MapVal(vals map[string]Value) Value { if len(vals) == 0 { panic("must not call MapVal with empty map") } elementType := DynamicPseudoType rawMap := make(map[string]interface{}, len(vals)) for key, val := range vals { if elementType == DynamicPseudoType { elementType = val.ty } else if val.ty != DynamicPseudoType && !elementType.Equals(val.ty) { panic(fmt.Errorf( "inconsistent map element types (%#v then %#v)", elementType, val.ty, )) } rawMap[NormalizeString(key)] = val.v } return Value{ ty: Map(elementType), v: rawMap, } } // MapValEmpty returns an empty map of the given element type. func MapValEmpty(element Type) Value { return Value{ ty: Map(element), v: map[string]interface{}{}, } } // SetVal returns a Value of set type whose element type is defined by // the types of the given values, which must be homogenous. // // If the types are not all consistent (aside from elements that are of the // dynamic pseudo-type) then this function will panic. It will panic also // if the given list is empty, since then the element type cannot be inferred. // (See also SetValEmpty.) func SetVal(vals []Value) Value { if len(vals) == 0 { panic("must not call SetVal with empty slice") } elementType := DynamicPseudoType rawList := make([]interface{}, len(vals)) for i, val := range vals { if elementType == DynamicPseudoType { elementType = val.ty } else if val.ty != DynamicPseudoType && !elementType.Equals(val.ty) { panic(fmt.Errorf( "inconsistent set element types (%#v then %#v)", elementType, val.ty, )) } rawList[i] = val.v } rawVal := set.NewSetFromSlice(setRules{elementType}, rawList) return Value{ ty: Set(elementType), v: rawVal, } } // SetValFromValueSet returns a Value of set type based on an already-constructed // ValueSet. // // The element type of the returned value is the element type of the given // set. func SetValFromValueSet(s ValueSet) Value { ety := s.ElementType() rawVal := s.s.Copy() // copy so caller can't mutate what we wrap return Value{ ty: Set(ety), v: rawVal, } } // SetValEmpty returns an empty set of the given element type. func SetValEmpty(element Type) Value { return Value{ ty: Set(element), v: set.NewSet(setRules{element}), } } // CapsuleVal creates a value of the given capsule type using the given // wrapVal, which must be a pointer to a value of the capsule type's native // type. // // This function will panic if the given type is not a capsule type, if // the given wrapVal is not compatible with the given capsule type, or if // wrapVal is not a pointer. func CapsuleVal(ty Type, wrapVal interface{}) Value { if !ty.IsCapsuleType() { panic("not a capsule type") } wv := reflect.ValueOf(wrapVal) if wv.Kind() != reflect.Ptr { panic("wrapVal is not a pointer") } it := ty.typeImpl.(*capsuleType).GoType if !wv.Type().Elem().AssignableTo(it) { panic("wrapVal target is not compatible with the given capsule type") } return Value{ ty: ty, v: wrapVal, } }