Upgrade to 0.12

[github/fretlink/terraform-provider-statuscake.git] / vendor / github.com / zclconf / go-cty / cty / value_init.go

diff --git a/vendor/github.com/zclconf/go-cty/cty/value_init.go b/vendor/github.com/zclconf/go-cty/cty/value_init.go
index 495a83e610cc7344686199f8ddf51f9cac1d7387..3deeba3bd3f6af7f98f605eaa0520f227e5a27b6 100644 (file)
--- a/vendor/github.com/zclconf/go-cty/cty/value_init.go
+++ b/vendor/github.com/zclconf/go-cty/cty/value_init.go
@@ -30,6 +30,44 @@ func NumberVal(v *big.Float) Value {
        }
 }
 
+// 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 {