def _EvalLhsAndLookupArith(self, node):
# type: (arith_expr_t) -> Tuple[int, lvalue_t]
""" For x = y and x += y and ++x """
lval = self.EvalArithLhs(node, runtime.NO_SPID)
val = OldValue(lval, self.mem, self.exec_opts)
# BASH_LINENO, arr (array name with shopt -s compat_array), etc.
if val.tag_() in (value_e.MaybeStrArray, value_e.AssocArray
) and lval.tag_() == lvalue_e.Named:
named_lval = cast(lvalue__Named, lval)
if word_eval.CheckCompatArray(named_lval.name, self.exec_opts):
if val.tag_() == value_e.MaybeStrArray:
lval = lvalue.Indexed(named_lval.name, 0)
elif val.tag_() == value_e.AssocArray:
lval = lvalue.Keyed(named_lval.name, '0')
val = word_eval.ResolveCompatArray(val)
# This error message could be better, but we already have one
#if val.tag_() == value_e.MaybeStrArray:
# e_die("Can't use assignment like ++ or += on arrays")
span_id = location.SpanForArithExpr(node)
i = self._ValToIntOrError(val, span_id=span_id)
return i, lval
def EvalToInt(self, node):
# type: (arith_expr_t) -> int
"""Used externally by ${a[i+1]} and ${a:start:len}.
Also used internally.
"""
val = self.Eval(node)
# BASH_LINENO, arr (array name with shopt -s compat_array), etc.
if val.tag_() in (value_e.MaybeStrArray, value_e.AssocArray) and node.tag_() == arith_expr_e.VarRef:
tok = cast(Token, node)
if word_eval.CheckCompatArray(tok.val, self.exec_opts):
val = word_eval.ResolveCompatArray(val)
# TODO: Can we avoid the runtime cost of adding location info?
span_id = location.SpanForArithExpr(node)
i = self._ValToIntOrError(val, span_id=span_id)
return i
