| 1 | from __future__ import print_function
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| 2 | 
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| 3 | from errno import EINTR
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| 4 | 
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| 5 | from _devbuild.gen.syntax_asdl import loc, loc_t, command_t
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| 6 | from _devbuild.gen.value_asdl import (value, value_e, value_t, eggex_ops,
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| 7 |                                       eggex_ops_t, regex_match, RegexMatch)
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| 8 | from core import error
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| 9 | from core.error import e_die
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| 10 | from core import ui
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| 11 | from mycpp import mops
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| 12 | from mycpp import mylib
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| 13 | from mycpp.mylib import tagswitch, log
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| 14 | from ysh import regex_translate
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| 15 | 
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| 16 | from typing import TYPE_CHECKING, cast, Dict, List, Optional
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| 17 | 
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| 18 | import libc
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| 19 | import posix_ as posix
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| 20 | 
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| 21 | _ = log
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| 22 | 
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| 23 | if TYPE_CHECKING:
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| 24 |     from core import state
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| 25 | 
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| 26 | 
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| 27 | def ToInt(val, msg, blame_loc):
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| 28 |     # type: (value_t, str, loc_t) -> int
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| 29 |     UP_val = val
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| 30 |     if val.tag() == value_e.Int:
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| 31 |         val = cast(value.Int, UP_val)
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| 32 |         return mops.BigTruncate(val.i)
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| 33 | 
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| 34 |     raise error.TypeErr(val, msg, blame_loc)
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| 35 | 
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| 36 | 
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| 37 | def ToFloat(val, msg, blame_loc):
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| 38 |     # type: (value_t, str, loc_t) -> float
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| 39 |     UP_val = val
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| 40 |     if val.tag() == value_e.Float:
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| 41 |         val = cast(value.Float, UP_val)
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| 42 |         return val.f
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| 43 | 
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| 44 |     raise error.TypeErr(val, msg, blame_loc)
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| 45 | 
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| 46 | 
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| 47 | def ToStr(val, msg, blame_loc):
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| 48 |     # type: (value_t, str, loc_t) -> str
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| 49 |     UP_val = val
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| 50 |     if val.tag() == value_e.Str:
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| 51 |         val = cast(value.Str, UP_val)
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| 52 |         return val.s
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| 53 | 
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| 54 |     raise error.TypeErr(val, msg, blame_loc)
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| 55 | 
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| 56 | 
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| 57 | def ToList(val, msg, blame_loc):
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| 58 |     # type: (value_t, str, loc_t) -> List[value_t]
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| 59 |     UP_val = val
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| 60 |     if val.tag() == value_e.List:
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| 61 |         val = cast(value.List, UP_val)
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| 62 |         return val.items
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| 63 | 
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| 64 |     raise error.TypeErr(val, msg, blame_loc)
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| 65 | 
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| 66 | 
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| 67 | def ToDict(val, msg, blame_loc):
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| 68 |     # type: (value_t, str, loc_t) -> Dict[str, value_t]
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| 69 |     UP_val = val
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| 70 |     if val.tag() == value_e.Dict:
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| 71 |         val = cast(value.Dict, UP_val)
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| 72 |         return val.d
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| 73 | 
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| 74 |     raise error.TypeErr(val, msg, blame_loc)
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| 75 | 
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| 76 | 
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| 77 | def ToCommand(val, msg, blame_loc):
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| 78 |     # type: (value_t, str, loc_t) -> command_t
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| 79 |     UP_val = val
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| 80 |     if val.tag() == value_e.Command:
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| 81 |         val = cast(value.Command, UP_val)
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| 82 |         return val.c
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| 83 | 
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| 84 |     raise error.TypeErr(val, msg, blame_loc)
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| 85 | 
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| 86 | 
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| 87 | def Stringify(val, blame_loc, prefix=''):
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| 88 |     # type: (value_t, loc_t, str) -> str
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| 89 |     """
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| 90 |     Used by
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| 91 | 
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| 92 |     $[x]    stringify operator
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| 93 |     @[x]    expression splice - each element is stringified
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| 94 |     @x      splice value
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| 95 |     """
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| 96 |     if blame_loc is None:
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| 97 |         blame_loc = loc.Missing
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| 98 | 
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| 99 |     UP_val = val
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| 100 |     with tagswitch(val) as case:
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| 101 |         if case(value_e.Str):  # trivial case
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| 102 |             val = cast(value.Str, UP_val)
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| 103 |             return val.s
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| 104 | 
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| 105 |         elif case(value_e.Null):
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| 106 |             s = 'null'  # JSON spelling
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| 107 | 
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| 108 |         elif case(value_e.Bool):
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| 109 |             val = cast(value.Bool, UP_val)
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| 110 |             s = 'true' if val.b else 'false'  # JSON spelling
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| 111 | 
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| 112 |         elif case(value_e.Int):
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| 113 |             val = cast(value.Int, UP_val)
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| 114 |             # e.g. decimal '42', the only sensible representation
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| 115 |             s = mops.ToStr(val.i)
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| 116 | 
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| 117 |         elif case(value_e.Float):
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| 118 |             val = cast(value.Float, UP_val)
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| 119 |             # TODO: what precision does this have?
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| 120 |             # The default could be like awk or Python, and then we also allow
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| 121 |             # ${myfloat %.3f} and more.
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| 122 |             # Python 3 seems to give a few more digits than Python 2 for str(1.0/3)
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| 123 |             s = str(val.f)
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| 124 | 
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| 125 |         elif case(value_e.Eggex):
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| 126 |             val = cast(value.Eggex, UP_val)
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| 127 |             s = regex_translate.AsPosixEre(val)  # lazily converts to ERE
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| 128 | 
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| 129 |         elif case(value_e.List):
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| 130 |             raise error.TypeErrVerbose(
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| 131 |                 "%sgot a List, which can't be stringified. Perhaps use @ instead of $, or use join()"
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| 132 |                 % prefix, blame_loc)
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| 133 | 
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| 134 |         else:
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| 135 |             raise error.TypeErr(
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| 136 |                 val, "%sexpected Null, Bool, Int, Float, Eggex" % prefix,
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| 137 |                 blame_loc)
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| 138 | 
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| 139 |     return s
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| 140 | 
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| 141 | 
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| 142 | def ToShellArray(val, blame_loc, prefix=''):
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| 143 |     # type: (value_t, loc_t, str) -> List[str]
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| 144 |     """
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| 145 |     Used by
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| 146 | 
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| 147 |     @[x]  expression splice
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| 148 |     @x    splice value
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| 149 | 
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| 150 |     Dicts do NOT get spliced, but they iterate over their keys
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| 151 |     So this function NOT use Iterator.
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| 152 |     """
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| 153 |     UP_val = val
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| 154 |     with tagswitch(val) as case2:
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| 155 |         if case2(value_e.List):
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| 156 |             val = cast(value.List, UP_val)
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| 157 |             strs = []  # type: List[str]
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| 158 |             # Note: it would be nice to add the index to the error message
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| 159 |             # prefix, WITHOUT allocating a string for every item
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| 160 |             for item in val.items:
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| 161 |                 strs.append(Stringify(item, blame_loc, prefix=prefix))
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| 162 | 
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| 163 |         # I thought about getting rid of this to keep OSH and YSH separate,
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| 164 |         # but:
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| 165 |         # - readarray/mapfile returns bash array (ysh-user-feedback depends on it)
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| 166 |         # - ysh-options tests parse_at too
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| 167 |         elif case2(value_e.BashArray):
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| 168 |             val = cast(value.BashArray, UP_val)
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| 169 |             strs = val.strs
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| 170 | 
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| 171 |         else:
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| 172 |             raise error.TypeErr(val, "%sexpected List" % prefix, blame_loc)
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| 173 | 
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| 174 |     return strs
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| 175 | 
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| 176 | 
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| 177 | class Iterator(object):
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| 178 |     """Interface for various types of for loop."""
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| 179 | 
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| 180 |     def __init__(self):
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| 181 |         # type: () -> None
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| 182 |         self.i = 0
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| 183 | 
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| 184 |     def Index(self):
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| 185 |         # type: () -> int
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| 186 |         return self.i
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| 187 | 
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| 188 |     def Next(self):
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| 189 |         # type: () -> None
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| 190 |         self.i += 1
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| 191 | 
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| 192 |     def FirstValue(self):
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| 193 |         # type: () -> Optional[value_t]
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| 194 |         """Return a value, or None if done
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| 195 | 
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| 196 |         e.g. return Dict key or List value
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| 197 |         """
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| 198 |         raise NotImplementedError()
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| 199 | 
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| 200 |     def SecondValue(self):
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| 201 |         # type: () -> value_t
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| 202 |         """Return Dict value or FAIL"""
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| 203 |         raise AssertionError("Shouldn't have called this")
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| 204 | 
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| 205 | 
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| 206 | class StdinIterator(Iterator):
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| 207 |     """ for x in <> { """
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| 208 | 
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| 209 |     def __init__(self, blame_loc):
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| 210 |         # type: (loc_t) -> None
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| 211 |         Iterator.__init__(self)
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| 212 |         self.blame_loc = blame_loc
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| 213 |         self.f = mylib.Stdin()
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| 214 | 
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| 215 |     def FirstValue(self):
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| 216 |         # type: () -> Optional[value_t]
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| 217 | 
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| 218 |         # line, eof = read_osh.ReadLineSlowly(None, with_eol=False)
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| 219 |         try:
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| 220 |             line = self.f.readline()
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| 221 |         except (IOError, OSError) as e:  # signals
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| 222 |             if e.errno == EINTR:
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| 223 |                 # Caller will can run traps with cmd_ev, like ReadLineSlowly
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| 224 |                 return value.Interrupted
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| 225 |             else:
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| 226 |                 # For possible errors from f.readline(), see
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| 227 |                 #   man read
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| 228 |                 #   man getline
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| 229 |                 # e.g.
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| 230 |                 # - ENOMEM getline() allocation failure
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| 231 |                 # - EISDIR getline() read from directory descriptor!
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| 232 |                 #
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| 233 |                 # Note: the read builtin returns status 1 for EISDIR.
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| 234 |                 #
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| 235 |                 # We'll raise a top-level error like Python.  (Awk prints a
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| 236 |                 # warning message)
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| 237 |                 e_die("I/O error in for <> loop: %s" % posix.strerror(e.errno),
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| 238 |                       self.blame_loc)
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| 239 | 
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| 240 |         if len(line) == 0:
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| 241 |             return None  # Done
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| 242 |         elif line.endswith('\n'):
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| 243 |             # TODO: optimize this to prevent extra garbage
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| 244 |             line = line[:-1]
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| 245 | 
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| 246 |         return value.Str(line)
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| 247 | 
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| 248 | 
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| 249 | class ArrayIter(Iterator):
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| 250 |     """ for x in 1 2 3 { """
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| 251 | 
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| 252 |     def __init__(self, strs):
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| 253 |         # type: (List[str]) -> None
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| 254 |         Iterator.__init__(self)
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| 255 |         self.strs = strs
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| 256 |         self.n = len(strs)
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| 257 | 
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| 258 |     def FirstValue(self):
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| 259 |         # type: () -> Optional[value_t]
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| 260 |         if self.i == self.n:
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| 261 |             return None
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| 262 |         return value.Str(self.strs[self.i])
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| 263 | 
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| 264 | 
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| 265 | class RangeIterator(Iterator):
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| 266 |     """ for x in (m:n) { """
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| 267 | 
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| 268 |     def __init__(self, val):
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| 269 |         # type: (value.Range) -> None
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| 270 |         Iterator.__init__(self)
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| 271 |         self.val = val
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| 272 | 
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| 273 |     def FirstValue(self):
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| 274 |         # type: () -> Optional[value_t]
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| 275 |         if self.val.lower + self.i >= self.val.upper:
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| 276 |             return None
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| 277 | 
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| 278 |         # TODO: range should be BigInt too
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| 279 |         return value.Int(mops.IntWiden(self.val.lower + self.i))
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| 280 | 
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| 281 | 
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| 282 | class ListIterator(Iterator):
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| 283 |     """ for x in (mylist) { """
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| 284 | 
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| 285 |     def __init__(self, val):
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| 286 |         # type: (value.List) -> None
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| 287 |         Iterator.__init__(self)
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| 288 |         self.val = val
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| 289 |         self.n = len(val.items)
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| 290 | 
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| 291 |     def FirstValue(self):
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| 292 |         # type: () -> Optional[value_t]
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| 293 |         if self.i == self.n:
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| 294 |             return None
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| 295 |         return self.val.items[self.i]
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| 296 | 
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| 297 | 
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| 298 | class DictIterator(Iterator):
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| 299 |     """ for x in (mydict) { """
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| 300 | 
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| 301 |     def __init__(self, val):
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| 302 |         # type: (value.Dict) -> None
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| 303 |         Iterator.__init__(self)
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| 304 | 
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| 305 |         # TODO: Don't materialize these Lists
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| 306 |         self.keys = val.d.keys()  # type: List[str]
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| 307 |         self.values = val.d.values()  # type: List[value_t]
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| 308 | 
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| 309 |         self.n = len(val.d)
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| 310 |         assert self.n == len(self.keys)
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| 311 | 
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| 312 |     def FirstValue(self):
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| 313 |         # type: () -> value_t
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| 314 |         if self.i == self.n:
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| 315 |             return None
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| 316 |         return value.Str(self.keys[self.i])
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| 317 | 
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| 318 |     def SecondValue(self):
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| 319 |         # type: () -> value_t
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| 320 |         return self.values[self.i]
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| 321 | 
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| 322 | 
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| 323 | def ToBool(val):
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| 324 |     # type: (value_t) -> bool
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| 325 |     """Convert any value to a boolean.
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| 326 | 
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| 327 |     TODO: expose this as Bool(x), like Python's bool(x).
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| 328 |     """
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| 329 |     UP_val = val
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| 330 |     with tagswitch(val) as case:
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| 331 |         if case(value_e.Undef):
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| 332 |             return False
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| 333 | 
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| 334 |         elif case(value_e.Null):
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| 335 |             return False
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| 336 | 
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| 337 |         elif case(value_e.Str):
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| 338 |             val = cast(value.Str, UP_val)
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| 339 |             return len(val.s) != 0
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| 340 | 
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| 341 |         # OLD TYPES
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| 342 |         elif case(value_e.BashArray):
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| 343 |             val = cast(value.BashArray, UP_val)
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| 344 |             return len(val.strs) != 0
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| 345 | 
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| 346 |         elif case(value_e.BashAssoc):
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| 347 |             val = cast(value.BashAssoc, UP_val)
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| 348 |             return len(val.d) != 0
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| 349 | 
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| 350 |         elif case(value_e.Bool):
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| 351 |             val = cast(value.Bool, UP_val)
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| 352 |             return val.b
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| 353 | 
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| 354 |         elif case(value_e.Int):
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| 355 |             val = cast(value.Int, UP_val)
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| 356 |             return not mops.Equal(val.i, mops.BigInt(0))
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| 357 | 
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| 358 |         elif case(value_e.Float):
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| 359 |             val = cast(value.Float, UP_val)
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| 360 |             return val.f != 0.0
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| 361 | 
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| 362 |         elif case(value_e.List):
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| 363 |             val = cast(value.List, UP_val)
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| 364 |             return len(val.items) > 0
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| 365 | 
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| 366 |         elif case(value_e.Dict):
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| 367 |             val = cast(value.Dict, UP_val)
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| 368 |             return len(val.d) > 0
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| 369 | 
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| 370 |         else:
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| 371 |             return True  # all other types are Truthy
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| 372 | 
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| 373 | 
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| 374 | def ExactlyEqual(left, right, blame_loc):
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| 375 |     # type: (value_t, value_t, loc_t) -> bool
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| 376 |     if left.tag() != right.tag():
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| 377 |         return False
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| 378 | 
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| 379 |     UP_left = left
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| 380 |     UP_right = right
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| 381 |     with tagswitch(left) as case:
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| 382 |         if case(value_e.Undef):
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| 383 |             return True  # there's only one Undef
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| 384 | 
 | 
| 385 |         elif case(value_e.Null):
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| 386 |             return True  # there's only one Null
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| 387 | 
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| 388 |         elif case(value_e.Bool):
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| 389 |             left = cast(value.Bool, UP_left)
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| 390 |             right = cast(value.Bool, UP_right)
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| 391 |             return left.b == right.b
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| 392 | 
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| 393 |         elif case(value_e.Int):
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| 394 |             left = cast(value.Int, UP_left)
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| 395 |             right = cast(value.Int, UP_right)
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| 396 |             return mops.Equal(left.i, right.i)
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| 397 | 
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| 398 |         elif case(value_e.Float):
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| 399 |             # Note: could provide floatEquals(), and suggest it
 | 
| 400 |             # Suggested idiom is abs(f1 - f2) < 0.1
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| 401 |             raise error.TypeErrVerbose("Equality isn't defined on Float",
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| 402 |                                        blame_loc)
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| 403 | 
 | 
| 404 |         elif case(value_e.Str):
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| 405 |             left = cast(value.Str, UP_left)
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| 406 |             right = cast(value.Str, UP_right)
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| 407 |             return left.s == right.s
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| 408 | 
 | 
| 409 |         elif case(value_e.BashArray):
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| 410 |             left = cast(value.BashArray, UP_left)
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| 411 |             right = cast(value.BashArray, UP_right)
 | 
| 412 |             if len(left.strs) != len(right.strs):
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| 413 |                 return False
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| 414 | 
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| 415 |             for i in xrange(0, len(left.strs)):
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| 416 |                 if left.strs[i] != right.strs[i]:
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| 417 |                     return False
 | 
| 418 | 
 | 
| 419 |             return True
 | 
| 420 | 
 | 
| 421 |         elif case(value_e.List):
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| 422 |             left = cast(value.List, UP_left)
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| 423 |             right = cast(value.List, UP_right)
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| 424 |             if len(left.items) != len(right.items):
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| 425 |                 return False
 | 
| 426 | 
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| 427 |             for i in xrange(0, len(left.items)):
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| 428 |                 if not ExactlyEqual(left.items[i], right.items[i], blame_loc):
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| 429 |                     return False
 | 
| 430 | 
 | 
| 431 |             return True
 | 
| 432 | 
 | 
| 433 |         elif case(value_e.BashAssoc):
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| 434 |             left = cast(value.Dict, UP_left)
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| 435 |             right = cast(value.Dict, UP_right)
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| 436 |             if len(left.d) != len(right.d):
 | 
| 437 |                 return False
 | 
| 438 | 
 | 
| 439 |             for k in left.d.keys():
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| 440 |                 if k not in right.d or right.d[k] != left.d[k]:
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| 441 |                     return False
 | 
| 442 | 
 | 
| 443 |             return True
 | 
| 444 | 
 | 
| 445 |         elif case(value_e.Dict):
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| 446 |             left = cast(value.Dict, UP_left)
 | 
| 447 |             right = cast(value.Dict, UP_right)
 | 
| 448 |             if len(left.d) != len(right.d):
 | 
| 449 |                 return False
 | 
| 450 | 
 | 
| 451 |             for k in left.d.keys():
 | 
| 452 |                 if (k not in right.d or
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| 453 |                         not ExactlyEqual(right.d[k], left.d[k], blame_loc)):
 | 
| 454 |                     return False
 | 
| 455 | 
 | 
| 456 |             return True
 | 
| 457 | 
 | 
| 458 |     raise error.TypeErrVerbose(
 | 
| 459 |         "Can't compare two values of type %s" % ui.ValType(left), blame_loc)
 | 
| 460 | 
 | 
| 461 | 
 | 
| 462 | def Contains(needle, haystack):
 | 
| 463 |     # type: (value_t, value_t) -> bool
 | 
| 464 |     """Haystack must be a Dict.
 | 
| 465 | 
 | 
| 466 |     We should have mylist->find(x) !== -1 for searching through a List.
 | 
| 467 |     Things with different perf characteristics should look different.
 | 
| 468 |     """
 | 
| 469 |     UP_haystack = haystack
 | 
| 470 |     with tagswitch(haystack) as case:
 | 
| 471 |         if case(value_e.Dict):
 | 
| 472 |             haystack = cast(value.Dict, UP_haystack)
 | 
| 473 |             s = ToStr(needle, "LHS of 'in' should be Str", loc.Missing)
 | 
| 474 |             return s in haystack.d
 | 
| 475 | 
 | 
| 476 |         else:
 | 
| 477 |             raise error.TypeErr(haystack, "RHS of 'in' should be Dict",
 | 
| 478 |                                 loc.Missing)
 | 
| 479 | 
 | 
| 480 |     return False
 | 
| 481 | 
 | 
| 482 | 
 | 
| 483 | def MatchRegex(left, right, mem):
 | 
| 484 |     # type: (value_t, value_t, Optional[state.Mem]) -> bool
 | 
| 485 |     """
 | 
| 486 |     Args:
 | 
| 487 |       mem: Whether to set or clear matches
 | 
| 488 |     """
 | 
| 489 |     UP_right = right
 | 
| 490 | 
 | 
| 491 |     with tagswitch(right) as case:
 | 
| 492 |         if case(value_e.Str):  # plain ERE
 | 
| 493 |             right = cast(value.Str, UP_right)
 | 
| 494 | 
 | 
| 495 |             right_s = right.s
 | 
| 496 |             regex_flags = 0
 | 
| 497 |             capture = eggex_ops.No  # type: eggex_ops_t
 | 
| 498 | 
 | 
| 499 |         elif case(value_e.Eggex):
 | 
| 500 |             right = cast(value.Eggex, UP_right)
 | 
| 501 | 
 | 
| 502 |             right_s = regex_translate.AsPosixEre(right)
 | 
| 503 |             regex_flags = regex_translate.LibcFlags(right.canonical_flags)
 | 
| 504 |             capture = eggex_ops.Yes(right.convert_funcs, right.convert_toks,
 | 
| 505 |                                     right.capture_names)
 | 
| 506 | 
 | 
| 507 |         else:
 | 
| 508 |             raise error.TypeErr(right, 'Expected Str or Regex for RHS of ~',
 | 
| 509 |                                 loc.Missing)
 | 
| 510 | 
 | 
| 511 |     UP_left = left
 | 
| 512 |     left_s = None  # type: str
 | 
| 513 |     with tagswitch(left) as case:
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| 514 |         if case(value_e.Str):
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| 515 |             left = cast(value.Str, UP_left)
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| 516 |             left_s = left.s
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| 517 |         else:
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| 518 |             raise error.TypeErrVerbose('LHS must be a string', loc.Missing)
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| 519 | 
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| 520 |     indices = libc.regex_search(right_s, regex_flags, left_s, 0)
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| 521 |     if indices is not None:
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| 522 |         if mem:
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| 523 |             mem.SetRegexMatch(RegexMatch(left_s, indices, capture))
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| 524 |         return True
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| 525 |     else:
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| 526 |         if mem:
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| 527 |             mem.SetRegexMatch(regex_match.No)
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| 528 |         return False
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| 529 | 
 | 
| 530 | 
 | 
| 531 | # vim: sw=4
 |