serene-golang-implementation/bootstrap/pkg/ast/location.go

99 lines
1.9 KiB
Go

/*
Serene --- Yet an other Lisp
Copyright (c) 2020 Sameer Rahmani <lxsameer@gnu.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package ast
type Location struct {
start int
end int
source Source
knownLocation bool
}
var UnknownLocation *Location = &Location{knownLocation: false}
func (l *Location) GetStart() int {
return l.start
}
func (l *Location) GetEnd() int {
return l.end
}
func (l *Location) GetSource() *Source {
if l.IsKnownLocaiton() {
return &l.source
}
return GetBuiltinSource()
}
func (l *Location) IncStart(x int) {
if x+l.start < len(*l.source.Buffer) {
l.start += x
} else {
l.start = len(*l.source.Buffer) - 1
}
}
func (l *Location) DecStart(x int) {
if l.start-x >= 0 {
l.start -= x
} else {
l.start = 0
}
}
func (l *Location) IncEnd(x int) {
if x+l.end < len(*l.source.Buffer) {
l.end += x
} else {
l.end = len(*l.source.Buffer) - 1
}
}
func (l *Location) DecEnd(x int) {
if l.end-x >= 0 {
l.end -= x
} else {
l.end = 0
}
}
func (l *Location) IsKnownLocaiton() bool {
return l.knownLocation
}
type ILocatable interface {
GetLocation() *Location
}
func MakeLocation(input *Source, start int, end int) *Location {
return &Location{
source: *input,
start: start,
end: end,
knownLocation: true,
}
}
func MakeUnknownLocation() *Location {
return UnknownLocation
}