Allow defaults in function signatures with syntax (..., p = e, ...).#30
Allow defaults in function signatures with syntax (..., p = e, ...).#30m-kurtenacker wants to merge 21 commits intomasterfrom
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There is a potential issue when the other parameters are bound to the default expression: This code causes the scoping to break, which can be observed by a number of free parameters being found during thorin's internal verification. |
Revert adding DefaultParamType. Instead, use CallExpr::infer. This only works if the parameter and argument lists materialize as tuples. Single parameters are not encapsulated like that and need special treatment later down the line.
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I changed the way defaults are propagated somewhat. The following example should work: Lines 1190 to 1191 in ed0d2d8 I don't know of any good ways to copy an ast::Node the way it would be required here. The way this is currently implemented generated multiple unique pointers to the same address, leading to undefined behavior. |
This syntax is used elsewhere as well, but very inconsistently. An alternative, at least on Linux/Mac, is to output to /dev/stdout instead.
multiple parameters as defaults.
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| T* operator->() const { return _ptr; } | ||
| T& operator*() const { return *_ptr; } | ||
| operator bool() const { return _ptr; } |
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better use
explicit operator bool() const { return _ptr; }This will disallow unintentional casts to bool but
if (ptr) { ... }is allowed!
| other._ptr = _ptr; | ||
| _ptr = tmp; | ||
| } | ||
| }; |
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the correct way to do it is like this:
friend template<class T> void swap(arena_ptr<T>& p, arena_ptr<T>& q) noexcept {
using std::swap;
swap(p.ptr, q.ptr);
}You want to have swap as a free function and make it available via ADL to others using swap. This is also why there is using std::swap: Either use the swap function provided via ADL for p.ptr or use std::swap as fallback,
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is this a correctness issue in the UB sense, or a stylistic issue ? this code is transitional and used only in one place, most likely I'll delete it soon anyhow
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Mostly a stylistic issue. But you want to make sure that - whenever you have another class that aggregates the arena_ptr (such as std::vector<arena_ptr<T>> - the correct swap is invoked. This will not happen if you make swap a member function. But in this particular case it doesn't matter much. So if it's transitional code anyway, no worries ...
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This hijacks the implicit summoning to also allow for defaults to be specified. Type checking infers a type for the supplied expression first, and then checks that the parameter matches. As a consequence, the following variants are all valid: