Documentation
¶
Overview ¶
Package checked (operator/checked) implements operations bounded by limits that are robust in the event of integer overflow.
Note: Float variants are not fully tested yet.
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
var ( Int = Limits[int]{math.MinInt, math.MaxInt} Int8 = Limits[int8]{math.MinInt8, math.MaxInt8} Int16 = Limits[int16]{math.MinInt16, math.MaxInt16} Int32 = Limits[int32]{math.MinInt32, math.MaxInt32} Int64 = Limits[int64]{math.MinInt64, math.MaxInt64} Uint = Limits[uint]{0, math.MaxUint} Uint8 = Limits[uint8]{0, math.MaxUint8} Uint16 = Limits[uint16]{0, math.MaxUint16} Uint32 = Limits[uint32]{0, math.MaxUint32} Uint64 = Limits[uint64]{0, math.MaxUint64} Float32 = Limits[float32]{-math.MaxFloat32, math.MaxFloat32} Float64 = Limits[float64]{-math.MaxFloat64, math.MaxFloat64} )
Filled-in Limits about different types with minimum and maximum set to the largest range supported by the limit.
For signed integers, these are the appropriately sized math.MinInt and math.MaxInt constants. For unsigned integers, these are zero and the appropriately sized math.MaxUint constants. For floats, these are the appropriately sized negative and positive math.MaxFloat constants.
Functions ¶
func Abs ¶
Abs returns (positive i, true) iff both i and the result lie between min and max inclusive. Otherwise, returns (0, false).
func Add ¶
Add returns (a + b, true) iff a, b, and the result all lie between min and max inclusive, otherwise returns (0, false). This calculation is robust in the event of integer overflow.
func Inv ¶
Inv returns (-i, true) iff both i and the result lie between min and max inclusive. Otherwise, returns (0, false).
Types ¶
type Limits ¶
type Limits[N Number] struct { Min N Max N }
Limits are a pair of values defining a range between an (inclusive) minimum value and an (inclusive) maximum value.
Example ¶
ExampleLimits demonstrates checked subtraction against custom limits.
package main
import (
"fmt"
"github.com/tawesoft/golib/v2/operator/checked"
)
func main() {
// Call checked.Sub directly with min and max...
{
const min = 0
const max = 99
result, ok := checked.Sub(min, max, 10, 9)
fmt.Printf("checked.Sub(min, max, 10, 9): %d, ok?=%t\n", result, ok)
}
// Or define a custom limit and call the Sub() method...
{
limit := checked.Limits[int]{Min: 0, Max: 99}
result, ok := limit.Sub(10, 25)
fmt.Printf("limit.Sub(10, 25): %d, ok?=%t\n", result, ok)
}
}
Output: checked.Sub(min, max, 10, 9): 1, ok?=true limit.Sub(10, 25): 0, ok?=false
func GetLimits ¶
GetLimits returns a filled-in [Limit] representing the widest possible minimum and maximum values for a generic type.
func (Limits[I]) Abs ¶
Abs returns (positive i, true) iff both i and the result lie between the Limit min and max inclusive. Otherwise, returns (0, false).
func (Limits[I]) Add ¶
Add returns (a + b, true) iff a, b, and the result all lie between the Limit min and max inclusive, otherwise returns (0, false). This calculation is robust in the event of integer overflow.
func (Limits[I]) Inv ¶
Inv returns (-i, true) iff both i and the result lie between the Limit min and max inclusive. Otherwise, returns (0, false).
type Number ¶ added in v2.15.0
type Number interface {
constraints.Integer | constraints.Float
}
Number represents any number type that you can support arithmetic using standard Go operators (like a + b, or a ^ b) - i.e. integers & floats.
Source Files