go-common/app/admin/ep/melloi/service/proto/range.go
2019-04-22 18:49:16 +08:00

91 lines
2.6 KiB
Go

// Copyright (c) 2017 Ernest Micklei
//
// MIT License
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
package proto
import (
"fmt"
"strconv"
)
// Range is to specify number intervals (with special end value "max")
type Range struct {
From, To int
Max bool
}
// SourceRepresentation return a single number if from = to. Returns <from> to <to> otherwise unless Max then return <from> to max.
func (r Range) SourceRepresentation() string {
if r.Max {
return fmt.Sprintf("%d to max", r.From)
}
if r.From == r.To {
return strconv.Itoa(r.From)
}
return fmt.Sprintf("%d to %d", r.From, r.To)
}
// parseRanges is used to parse ranges for extensions and reserved
func parseRanges(p *Parser, n Visitee) (list []Range, err error) {
seenTo := false
for {
pos, tok, lit := p.next()
if isString(lit) {
return list, p.unexpected(lit, "integer, <to> <max>", n)
}
switch lit {
case ",":
case "to":
seenTo = true
case ";":
p.nextPut(pos, tok, lit) // allow for inline comment parsing
goto done
case "max":
if !seenTo {
return list, p.unexpected(lit, "to", n)
}
from := list[len(list)-1]
list = append(list[0:len(list)-1], Range{From: from.From, Max: true})
default:
// must be number
i, err := strconv.Atoi(lit)
if err != nil {
return list, p.unexpected(lit, "range integer", n)
}
if seenTo {
// replace last two ranges with one
if len(list) < 1 {
p.unexpected(lit, "integer", n)
}
from := list[len(list)-1]
list = append(list[0:len(list)-1], Range{From: from.From, To: i})
seenTo = false
} else {
list = append(list, Range{From: i, To: i})
}
}
}
done:
return
}