File size: 5,965 Bytes
ffaa9fc
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
#
# Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
# Use of this file is governed by the BSD 3-clause license that
# can be found in the LICENSE.txt file in the project root.
#

from io import StringIO
from antlr4.Token import Token

# need forward declarations
IntervalSet = None

class IntervalSet(object):
    __slots__ = ('intervals', 'readonly')

    def __init__(self):
        self.intervals = None
        self.readonly = False

    def __iter__(self):
        if self.intervals is not None:
            for i in self.intervals:
                for c in i:
                    yield c

    def __getitem__(self, item):
        i = 0
        for k in self:
            if i==item:
                return k
            else:
                i += 1
        return Token.INVALID_TYPE

    def addOne(self, v:int):
        self.addRange(range(v, v+1))

    def addRange(self, v:range):
        if self.intervals is None:
            self.intervals = list()
            self.intervals.append(v)
        else:
            # find insert pos
            k = 0
            for i in self.intervals:
                # distinct range -> insert
                if v.stop<i.start:
                    self.intervals.insert(k, v)
                    return
                # contiguous range -> adjust
                elif v.stop==i.start:
                    self.intervals[k] = range(v.start, i.stop)
                    return
                # overlapping range -> adjust and reduce
                elif v.start<=i.stop:
                    self.intervals[k] = range(min(i.start,v.start), max(i.stop,v.stop))
                    self.reduce(k)
                    return
                k += 1
            # greater than any existing
            self.intervals.append(v)

    def addSet(self, other:IntervalSet):
        if other.intervals is not None:
            for i in other.intervals:
                self.addRange(i)
        return self

    def reduce(self, k:int):
        # only need to reduce if k is not the last
        if k<len(self.intervals)-1:
            l = self.intervals[k]
            r = self.intervals[k+1]
            # if r contained in l
            if l.stop >= r.stop:
                self.intervals.pop(k+1)
                self.reduce(k)
            elif l.stop >= r.start:
                self.intervals[k] = range(l.start, r.stop)
                self.intervals.pop(k+1)

    def complement(self, start, stop):
        result = IntervalSet()
        result.addRange(range(start,stop+1))
        for i in self.intervals:
            result.removeRange(i)
        return result

    def __contains__(self, item):
        if self.intervals is None:
            return False
        else:
            return any(item in i for i in self.intervals)

    def __len__(self):
        return sum(len(i) for i in self.intervals)

    def removeRange(self, v):
        if v.start==v.stop-1:
            self.removeOne(v.start)
        elif self.intervals is not None:
            k = 0
            for i in self.intervals:
                # intervals are ordered
                if v.stop<=i.start:
                    return
                # check for including range, split it
                elif v.start>i.start and v.stop<i.stop:
                    self.intervals[k] = range(i.start, v.start)
                    x = range(v.stop, i.stop)
                    self.intervals.insert(k, x)
                    return
                # check for included range, remove it
                elif v.start<=i.start and v.stop>=i.stop:
                    self.intervals.pop(k)
                    k -= 1  # need another pass
                # check for lower boundary
                elif v.start<i.stop:
                    self.intervals[k] = range(i.start, v.start)
                # check for upper boundary
                elif v.stop<i.stop:
                    self.intervals[k] = range(v.stop, i.stop)
                k += 1

    def removeOne(self, v):
        if self.intervals is not None:
            k = 0
            for i in self.intervals:
                # intervals is ordered
                if v<i.start:
                    return
                # check for single value range
                elif v==i.start and v==i.stop-1:
                    self.intervals.pop(k)
                    return
                # check for lower boundary
                elif v==i.start:
                    self.intervals[k] = range(i.start+1, i.stop)
                    return
                # check for upper boundary
                elif v==i.stop-1:
                    self.intervals[k] = range(i.start, i.stop-1)
                    return
                # split existing range
                elif v<i.stop-1:
                    x = range(i.start, v)
                    self.intervals[k] = range(v + 1, i.stop)
                    self.intervals.insert(k, x)
                    return
                k += 1


    def toString(self, literalNames:list, symbolicNames:list):
        if self.intervals is None:
            return "{}"
        with StringIO() as buf:
            if len(self)>1:
                buf.write("{")
            first = True
            for i in self.intervals:
                for j in i:
                    if not first:
                        buf.write(", ")
                    buf.write(self.elementName(literalNames, symbolicNames, j))
                    first = False
            if len(self)>1:
                buf.write("}")
            return buf.getvalue()

    def elementName(self, literalNames:list, symbolicNames:list, a:int):
        if a==Token.EOF:
            return "<EOF>"
        elif a==Token.EPSILON:
            return "<EPSILON>"
        else:
            if a<len(literalNames) and literalNames[a] != "<INVALID>":
                return literalNames[a]
            if a<len(symbolicNames):
                return symbolicNames[a]
            return "<UNKNOWN>"