Table [tab:over.conversions]
summarizes the conversions defined in Clause [conv] and
partitions them into four disjoint categories: Lvalue Transformation,
Qualification Adjustment, Promotion, and Conversion.
[ *Note:*
These categories are orthogonal with respect to value category,
cv-qualification, and data representation: the Lvalue Transformations
do not change the cv-qualification or data
representation of the type; the Qualification Adjustments do not
change the value category or data representation of the type; and
the Promotions and Conversions do not change the
value category or cv-qualification of the type.
* — end note* ]

[ *Note:*
As described in Clause [conv],
a standard conversion sequence is either the Identity conversion
by itself (that is, no conversion) or consists of one to three
conversions from the other
four categories.
At most one conversion from each
category is allowed in a single standard conversion sequence.
If there are two or more conversions in the sequence, the
conversions are applied in the canonical order:
**Lvalue Transformation**,
**Promotion**
or
**Conversion**,
**Qualification Adjustment**.
* — end note* ]

Each conversion in Table [tab:over.conversions] also has an associated rank (Exact Match, Promotion, or Conversion). These are used to rank standard conversion sequences ([over.ics.rank]). The rank of a conversion sequence is determined by considering the rank of each conversion in the sequence and the rank of any reference binding ([over.ics.ref]). If any of those has Conversion rank, the sequence has Conversion rank; otherwise, if any of those has Promotion rank, the sequence has Promotion rank; otherwise, the sequence has Exact Match rank.

Table 12 — Conversions

Conversion | Category | Rank | Subclause |

No conversions required | Identity | ||

Lvalue-to-rvalue conversion | [conv.lval] | ||

Array-to-pointer conversion | Lvalue Transformation | Exact Match | [conv.array] |

Function-to-pointer conversion | [conv.func] | ||

Qualification conversions | Qualification Adjustment | [conv.qual] | |

Integral promotions | [conv.prom] | ||

Floating point promotion | Promotion | Promotion | [conv.fpprom] |

Integral conversions | [conv.integral] | ||

Floating point conversions | [conv.double] | ||

Floating-integral conversions | [conv.fpint] | ||

Pointer conversions | Conversion | Conversion | [conv.ptr] |

Pointer to member conversions | [conv.mem] | ||

Boolean conversions | [conv.bool] |