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Copy pathprint.go
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193 lines (179 loc) · 4.36 KB
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/*
* Copyright (c) 2022 The GoPlus Authors (goplus.org). All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package igop
import (
"bytes"
"fmt"
"reflect"
"unsafe"
)
// writevalue for write argument pass to print
func writevalue(buf *bytes.Buffer, v interface{}, enableAny bool) {
switch v := v.(type) {
case float64:
writefloat(buf, v)
case float32:
writefloat(buf, float64(v))
case complex128:
writecomplex(buf, v)
case complex64:
writecomplex(buf, complex128(v))
case nil, bool, int, int8, int16, int32, int64,
uint, uint8, uint16, uint32, uint64, uintptr,
string:
fmt.Fprintf(buf, "%v", v)
default:
i := reflect.ValueOf(v)
switch i.Kind() {
case reflect.Float32, reflect.Float64:
writefloat(buf, i.Float())
case reflect.Complex64, reflect.Complex128:
writecomplex(buf, i.Complex())
case reflect.Map, reflect.Ptr, reflect.Func, reflect.Chan, reflect.UnsafePointer:
fmt.Fprintf(buf, "%p", v)
case reflect.Slice:
fmt.Fprintf(buf, "[%v/%v]%p", i.Len(), i.Cap(), v)
case reflect.String:
fmt.Fprintf(buf, "%v", v)
case reflect.Interface:
eface := *(*emptyInterface)(unsafe.Pointer(&i))
fmt.Fprintf(buf, "(%p,%p)", eface.typ, eface.word)
case reflect.Struct, reflect.Array:
if enableAny {
fmt.Fprintf(buf, "%v", v)
} else {
panic(fmt.Sprintf("illegal types for operand: print\n\t%T", v))
}
default:
fmt.Fprintf(buf, "%v", v)
}
}
}
// emptyInterface is the header for an interface{} value.
type emptyInterface struct {
typ unsafe.Pointer
word unsafe.Pointer
}
func writeinterface(out *bytes.Buffer, i interface{}) {
eface := *(*emptyInterface)(unsafe.Pointer(&i))
fmt.Fprintf(out, "(%p,%p)", eface.typ, eface.word)
}
func writecomplex(out *bytes.Buffer, c complex128) {
out.WriteByte('(')
writefloat(out, real(c))
writefloat(out, imag(c))
out.WriteString("i)")
}
func writefloat(out *bytes.Buffer, v float64) {
switch {
case v != v:
out.WriteString("NaN")
return
case v+v == v && v > 0:
out.WriteString("+Inf")
return
case v+v == v && v < 0:
out.WriteString("-Inf")
return
}
const n = 7 // digits printed
var buf [n + 7]byte
buf[0] = '+'
e := 0 // exp
if v == 0 {
if 1/v < 0 {
buf[0] = '-'
}
} else {
if v < 0 {
v = -v
buf[0] = '-'
}
// normalize
for v >= 10 {
e++
v /= 10
}
for v < 1 {
e--
v *= 10
}
// round
h := 5.0
for i := 0; i < n; i++ {
h /= 10
}
v += h
if v >= 10 {
e++
v /= 10
}
}
// format +d.dddd+edd
for i := 0; i < n; i++ {
s := int(v)
buf[i+2] = byte(s + '0')
v -= float64(s)
v *= 10
}
buf[1] = buf[2]
buf[2] = '.'
buf[n+2] = 'e'
buf[n+3] = '+'
if e < 0 {
e = -e
buf[n+3] = '-'
}
buf[n+4] = byte(e/100) + '0'
buf[n+5] = byte(e/10)%10 + '0'
buf[n+6] = byte(e%10) + '0'
out.Write(buf[:])
}
// writeany for write argument pass to panic
func writeany(buf *bytes.Buffer, v interface{}) {
switch v := v.(type) {
case nil, bool, int, int8, int16, int32, int64,
float32, float64, complex64, complex128,
uint, uint8, uint16, uint32, uint64, uintptr,
string:
writevalue(buf, v, true)
case error:
fmt.Fprintf(buf, "%v", v)
default:
i := reflect.ValueOf(v)
typ := i.Type()
switch i.Kind() {
case reflect.String:
fmt.Fprintf(buf, "%v(%q)", typ, i)
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
fmt.Fprintf(buf, "%v(%v)", typ, i)
case reflect.Float32, reflect.Float64:
buf.WriteString(typ.String())
buf.WriteByte('(')
writefloat(buf, i.Float())
buf.WriteByte(')')
case reflect.Complex64, reflect.Complex128:
buf.WriteString(typ.String())
buf.WriteByte('(')
writecomplex(buf, i.Complex())
buf.WriteByte(')')
default:
eface := *(*emptyInterface)(unsafe.Pointer(&i))
fmt.Fprintf(buf, "(%v) %p", typ, eface.word)
}
}
}