doc: update documentation as errors messages changed

README.md

@@ -5,11 +5,11 @@
 [![codecov](https://codecov.io/gh/ccoVeille/go-safecast/graph/badge.svg?token=VW0VO503U6)](https://codecov.io/gh/ccoVeille/go-safecast)
 [![Code Climate](https://codeclimate.com/github/ccoVeille/go-safecast.png)](https://codeclimate.com/github/ccoVeille/go-safecast)
 
-## Project purpose
+go-safecast solves the type conversion issues in Go
 
 In Go, integer type conversion can lead to a silent and unexpected behavior and errors if not handled carefully.
 
-This package is made to help to convert any number to another, and report an error when if there would be a [loss or overflow in the conversion](#conversion-overflows)
+This package helps to convert any number to another, and report an error when if there would be a [loss or overflow in the conversion](#conversion-issues)
 
 ## Usage
 
@@ -24,42 +24,41 @@ import (
 )
 
 func main() {
-
   // when there is no overflow
   //
-  fmt.Println(safecast.ToInt8(float64(42)))
+  fmt.Println(safecast.ToInt8(float64(42.42)))
   // Output: 42, nil
   fmt.Println(safecast.ToInt8(int64(-1)))
   // Output: -1, nil
 
   // when there is an overflow
   //
-  fmt.Println(safecast.ToInt8(float64(20000)))
-  // Output: 0 conversion issue: 20000 is greater than 127
+  fmt.Println(safecast.ToInt8(float64(200.42)))
+  // Output: 0 conversion issue: 200.42 (float64) is greater than 127 (int8): maximum value for this type exceeded
   fmt.Println(safecast.ToUint8(int64(-1)))
-  // Output: 0 conversion issue: -1 is negative
+  // Output: 0 conversion issue: -1 (int64) is less than 0 (uint8): minimum value for this type exceeded
   fmt.Println(safecast.ToInt16(int32(40000)))
-  // Output: 0 conversion issue: 40000 is greater than 32767
+  // Output: 0 conversion issue: 40000 (int32) is greater than 32767 (int16): maximum value for this type exceeded
   fmt.Println(safecast.ToUint16(int64(-1)))
-  // Output: 0 conversion issue: -1 is negative
+  // Output: 0 conversion issue: -1 (int64) is less than 0 (uint16): minimum value for this type exceeded
   fmt.Println(safecast.ToInt32(math.MaxUint32 + 1))
-  // Output: 0 conversion issue: 4294967296 is greater than 2147483647
+  // Output: 0 conversion issue: 4294967296 (int) is greater than 2147483647 (int32): maximum value for this type exceeded
   fmt.Println(safecast.ToUint32(int64(-1)))
-  // Output: 0 conversion issue: -1 is negative
+  // Output: 0 conversion issue: -1 (int64) is less than 0 (uint32): minimum value for this type exceeded
   fmt.Println(safecast.ToInt64(uint64(math.MaxInt64) + 1))
-  // Output: 0 conversion issue: 9223372036854775808 is greater than 9223372036854775807
+  // Output: 0 conversion issue: 9223372036854775808 (uint64) is greater than 9223372036854775807 (int64): maximum value for this type exceeded
   fmt.Println(safecast.ToUint64(int8(-1)))
-  // Output: 0 conversion issue: -1 is negative
+  // Output: 0 conversion issue: -1 (int8) is less than 0 (uint64): minimum value for this type exceeded
   fmt.Println(safecast.ToInt(uint64(math.MaxInt) + 1))
-  // Output: 0 conversion issue: 9223372036854775808 is greater than 9223372036854775807
+  // Output: 0 conversion issue: 9223372036854775808 (uint64) is greater than 9223372036854775807 (int): maximum value for this type exceeded
   fmt.Println(safecast.ToUint(int8(-1)))
-  // Output: 0 conversion issue: -1 is negative
+  // Output: 0 conversion issue: -1 (int8) is less than 0 (uint): minimum value for this type exceeded
 }
 ```
 
-[Go Playground](https://go.dev/play/p/VCrv1aLJjMQ)
+[Go Playground](https://go.dev/play/p/tG2PYedrZJL)
 
-## Conversion overflows
+## Conversion issues
 
 Issues can happen when converting between signed and unsigned integers, or when converting to a smaller integer type.
 

conversion.go

@@ -1,4 +1,4 @@
-// Package safecast aims to solve the issue of type conversion
+// Package go-safecast solves the type conversion issues in Go
 //
 // In Go, integer type conversion can lead to unexpected behavior and errors if not handled carefully.
 // Issues can happen when converting between signed and unsigned integers, or when converting to a smaller integer type.

examples_test.go

@@ -0,0 +1,58 @@
+package safecast_test
+
+import (
+	"fmt"
+	"math"
+
+	"github.com/ccoveille/go-safecast"
+)
+
+func ExampleToInt8() {
+	fmt.Println(safecast.ToInt8(float64(200.42)))
+	// Output: 0 conversion issue: 200.42 (float64) is greater than 127 (int8): maximum value for this type exceeded
+}
+
+func ExampleToUint8() {
+	fmt.Println(safecast.ToUint8(int64(-1)))
+	// Output: 0 conversion issue: -1 (int64) is less than 0 (uint8): minimum value for this type exceeded
+}
+
+func ExampleToInt16() {
+	fmt.Println(safecast.ToInt16(int32(40000)))
+	// Output: 0 conversion issue: 40000 (int32) is greater than 32767 (int16): maximum value for this type exceeded
+}
+
+func ExampleToUint16() {
+	fmt.Println(safecast.ToUint16(int64(-1)))
+	// Output: 0 conversion issue: -1 (int64) is less than 0 (uint16): minimum value for this type exceeded
+}
+
+func ExampleToInt32() {
+	fmt.Println(safecast.ToInt32(math.MaxUint32 + 1))
+	// Output: 0 conversion issue: 4294967296 (int) is greater than 2147483647 (int32): maximum value for this type exceeded
+}
+
+func ExampleToUint32() {
+	fmt.Println(safecast.ToUint32(int64(-1)))
+	// Output: 0 conversion issue: -1 (int64) is less than 0 (uint32): minimum value for this type exceeded
+}
+
+func ExampleToInt64() {
+	fmt.Println(safecast.ToInt64(uint64(math.MaxInt64) + 1))
+	// Output: 0 conversion issue: 9223372036854775808 (uint64) is greater than 9223372036854775807 (int64): maximum value for this type exceeded
+}
+
+func ExampleToUint64() {
+	fmt.Println(safecast.ToUint64(int8(-1)))
+	// Output: 0 conversion issue: -1 (int8) is less than 0 (uint64): minimum value for this type exceeded
+}
+
+func ExampleToInt() {
+	fmt.Println(safecast.ToInt(uint64(math.MaxInt) + 1))
+	// Output: 0 conversion issue: 9223372036854775808 (uint64) is greater than 9223372036854775807 (int): maximum value for this type exceeded
+}
+
+func ExampleToUint() {
+	fmt.Println(safecast.ToUint(int8(-1)))
+	// Output: 0 conversion issue: -1 (int8) is less than 0 (uint): minimum value for this type exceeded
+}