31 Input/output library [input.output]

31.5 Iostreams base classes [iostreams.base]

31.5.3 Class template fpos[fpos]

31.5.3.2 Requirements [fpos.operations]

Table 126: Position type requirements [tab:fpos.operations]
 ðŸ”— Expression Return type Operational Assertion/note ðŸ”— semantics pre-/post-condition ðŸ”— P(o) P converts from offset Effects: Value-initializes the state object. ðŸ”— P p(o);P p = o; Effects: Value-initializes the state object. Postconditions: p == P(o) is true. ðŸ”— P() P P(0) ðŸ”— P p; P p(0); ðŸ”— O(p) streamoff converts to offset P(O(p)) == p ðŸ”— p == q bool Remarks: For any two values o and o2, if p is obtained from o converted to P or from a copy of such P value and if q is obtained from o2 converted to P or from a copy of such P value, then p == q is true only if o == o2 is true. ðŸ”— p != q bool !(p == q) ðŸ”— p + o P + offset Remarks: With ql = p + o;, then: ql - o == p ðŸ”— pl += o P& += offset Remarks: With ql = pl; before the +=, then: pl - o == ql ðŸ”— p - o P - offset Remarks: With ql = p - o;, then: ql + o == p ðŸ”— pl -= o P& -= offset Remarks: With ql = pl; before the -=, then: pl + o == ql ðŸ”— o + p convertible to P p + o P(o + p) == p + o ðŸ”— p - q streamoff distance p == q + (p - q)