README
¶
erf
Package erf provides error management with stack trace. Erf is an error type that wraps the underlying error that stores and formats the stack trace. Please see godoc.
Examples
To run any example, please use the command like the following:
cd examples/
go run example1.go
Tests
To run all tests, please use the following command:
go test -v
To run all examples, please use the following command:
go test -v -run=^Example
To run all benchmarks, please use the following command:
go test -v -run=^Benchmark -bench=.
Documentation
¶
Overview ¶
Package erf provides error management with stack trace.
Index ¶
- Variables
- func Errorf(format string, a ...interface{}) error
- func PC(size, skip int) []uintptr
- func Wrap(err error) error
- type Erf
- func (e *Erf) Arg(index int) interface{}
- func (e *Erf) Args() []interface{}
- func (e *Erf) Attach(tags ...string) *Erf
- func (e *Erf) Error() string
- func (e *Erf) Fmt() string
- func (e *Erf) Format(f fmt.State, verb rune)
- func (e *Erf) Len() int
- func (e *Erf) PC() []uintptr
- func (e *Erf) StackTrace() *StackTrace
- func (e *Erf) Tag(tag string) interface{}
- func (e *Erf) Unwrap() error
- type StackCaller
- type StackTrace
- type WrappedError
Examples ¶
Constants ¶
This section is empty.
Variables ¶
var ( // DefaultPCSize defines max length of Erf program counters in PC() method. DefaultPCSize = int(4096 / unsafe.Sizeof(uintptr(0))) )
Functions ¶
func Errorf ¶
Errorf is similar with Newf except that it returns the error interface instead of the Erf pointer.
Types ¶
type Erf ¶
type Erf struct {
// contains filtered or unexported fields
}
Erf is an error type that wraps the underlying error that stores and formats the stack trace.
Example ¶
package main
import (
"fmt"
"github.com/goinsane/erf"
)
func main() {
e := erf.New("an example erf error")
e2 := erf.Wrap(e)
fmt.Println("just show first error message (default: padding char '\\t', padding 0, indent 1)")
fmt.Printf("%s\n\n", e2)
fmt.Println("show error message with indent, append stack trace")
fmt.Printf("%+s\n\n", e2)
fmt.Println("show first error message with indent, append stack trace")
fmt.Printf("%+ s\n\n", e2)
fmt.Println("use file name as file path for StackCaller")
fmt.Printf("%+#s\n\n", e2)
fmt.Println("padding 2, indent 1 by default")
fmt.Printf("%+#2s\n\n", e2)
fmt.Println("padding 2, indent 3")
fmt.Printf("%+#2.3s\n\n", e2)
fmt.Println("use ' ' as padding char (padding 0, indent 2)")
fmt.Printf("%-s\n\n", e2)
fmt.Println("show error message with indent, append stack trace")
fmt.Printf("%-+s\n\n", e2)
fmt.Println("show first error message with indent, append stack trace")
fmt.Printf("%-+ s\n\n", e2)
fmt.Println("use file name as file path for StackCaller")
fmt.Printf("%-+#s\n\n", e2)
fmt.Println("padding 2, indent 2 by default")
fmt.Printf("%-+#2s\n\n", e2)
fmt.Println("padding 2, indent 3")
fmt.Printf("%-+#2.3s\n\n", e2)
}
func Newf ¶
Newf creates a new Erf object with the given format and args. It panics if an any arg is nil.
func (*Erf) Arg ¶
Arg returns an argument value on the given index. It panics if index is out of range.
func (*Erf) Args ¶
func (e *Erf) Args() []interface{}
Args returns all argument values. It returns nil if Erf didn't create with formatting functions.
func (*Erf) Attach ¶
Attach attaches tags to arguments, if arguments are given. It panics for given errors:
args are not using tags are already attached number of tags is more than args tag already defined
func (*Erf) Fmt ¶
Fmt returns the format argument of the formatting functions (Newf, Errorf or Wrap) that created Erf.
func (*Erf) Format ¶
Format is implementation of fmt.Formatter. Format lists all StackTrace's line by line with given format.
For '%s' (also '%v'):
%s just show first error message (default: padding char '\t', padding 0, indent 1) %+s show error message with indent, append stack trace using format '%+s' %#s use file name as file path for StackCaller %-s use ' ' as padding char (padding 0, indent 2) %0s show only first error even verb '+' was given % s exact with %0s %4s padding 4, default indent %.3s default padding, indent 3 %4.3s padding 4, indent 3 %4.s padding 4, indent 0
func (*Erf) StackTrace ¶
func (e *Erf) StackTrace() *StackTrace
StackTrace returns a StackTrace of Erf.
type StackCaller ¶
StackCaller stores the information of stack caller. StackCaller can format given information as string by using Format or String methods.
Example ¶
package main
import (
"fmt"
"github.com/goinsane/erf"
)
func main() {
e := erf.New("an example erf error")
sc := e.StackTrace().Caller(0)
fmt.Println("just show function and entry (default: padding char '\\t', padding 0, indent 1)")
fmt.Printf("%s\n\n", sc)
fmt.Println("show file path, line and pc")
fmt.Printf("%+s\n\n", sc)
fmt.Println("use file name as file path")
fmt.Printf("%+#s\n\n", sc)
fmt.Println("padding 2, indent 1 by default")
fmt.Printf("%+#2s\n\n", sc)
fmt.Println("padding 2, indent 3")
fmt.Printf("%+#2.3s\n\n", sc)
fmt.Println("use ' ' as padding char (padding 0, indent 2)")
fmt.Printf("%-s\n\n", sc)
fmt.Println("show file path, line and pc")
fmt.Printf("%-+s\n\n", sc)
fmt.Println("use file name as file path")
fmt.Printf("%-+#s\n\n", sc)
fmt.Println("padding 2, indent 2 by default")
fmt.Printf("%-+#2s\n\n", sc)
fmt.Println("padding 2, indent 3")
fmt.Printf("%-+#2.3s\n\n", sc)
}
func (StackCaller) Format ¶
func (c StackCaller) Format(f fmt.State, verb rune)
Format is implementation of fmt.Formatter.
For '%s' (also '%v'):
%s just show function and entry (default: padding char '\t', padding 0, indent 1) %+s show file path, line and pc %#s use file name as file path %-s use ' ' as padding char (padding 0, indent 2) %4s padding 4, default indent %.3s default padding, indent 3 %4.3s padding 4, indent 3 %4.s padding 4, indent 0
func (StackCaller) String ¶
func (c StackCaller) String() string
String is implementation of fmt.Stringer. It is synonym with fmt.Sprintf("%s", c).
type StackTrace ¶
type StackTrace struct {
// contains filtered or unexported fields
}
StackTrace stores the information of stack trace.
Example ¶
package main
import (
"fmt"
"github.com/goinsane/erf"
)
func main() {
e := erf.New("an example erf error")
st := e.StackTrace()
fmt.Println("default")
fmt.Printf("%s\n\n", st)
fmt.Println("show file path, line and pc")
fmt.Printf("%+s\n\n", st)
}
func NewStackTrace ¶
func NewStackTrace(pc ...uintptr) *StackTrace
NewStackTrace creates a new StackTrace object.
func (*StackTrace) Caller ¶
func (t *StackTrace) Caller(index int) StackCaller
Caller returns a StackCaller on the given index. It panics if index is out of range.
func (*StackTrace) Duplicate ¶
func (t *StackTrace) Duplicate() *StackTrace
Duplicate duplicates the StackTrace object.
func (*StackTrace) Format ¶
func (t *StackTrace) Format(f fmt.State, verb rune)
Format is implementation of fmt.Formatter. Format lists StackCaller's line by line with given format.
func (*StackTrace) Len ¶
func (t *StackTrace) Len() int
Len returns the length of the StackCaller slice.
func (*StackTrace) String ¶
func (t *StackTrace) String() string
String is implementation of fmt.Stringer. It is synonym with fmt.Sprintf("%s", t).
Source Files