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error: invalid old(..) expression in inline spec block
  ┌─ tests/sources/inline_spec_err.move:9:7
  │
9 │       assert old(a) == y;
  │       ^^^^^^^^^^^^^^^^^^^
  │       │          │
  │       │          this expression is not a function parameter
  │       only a function parameter is allowed in old(..) expressions in inline spec block

error: invalid old(..) expression in inline spec block
   ┌─ tests/sources/inline_spec_err.move:10:7
   │
10 │       assert old(b) == 0;
   │       ^^^^^^^^^^^^^^^^^^^
   │       │          │
   │       │          this expression is not a function parameter
   │       only a function parameter is allowed in old(..) expressions in inline spec block

error: invalid old(..) expression in inline spec block
   ┌─ tests/sources/inline_spec_err.move:11:7
   │
11 │       assert old(x != y);
   │       ^^^^^^^^^^^^^^^^^^^
   │       │          │
   │       │          this expression is not a function parameter
   │       only a function parameter is allowed in old(..) expressions in inline spec block