has parse parseAll parseOr parseOr parseSeq parseSeq parseSeqOr parseSeqOr parseStruct parseStructOr parseStructOr readAll readKeywords readKeywordsValues remove write write writeComment writeHistory writeSeq writeSeq writeSeqIn writeSeqIn

parseOr() [1/2] template<typename T > Record<T> Euclid::Fits::Header::parseOr ( const Record< T > &  fallback ) const Parse a record if it exists, return a fallback record otherwise. Template Parameters T The record value type Parameters keyword The record keyword fallback The fallback record, keyword of which is looked for There are two ways to parse a record: with or without a fallback, that is, a record which is returned if the specified keyword is not found in the header. Without a fallback, the expected return value type is provided as the template parameter. When a fallback is provided, the return type is the fallback type, by default, and the template parameter can be omitted. Example usages: // Parse a record Record<int> record = h.parse<int>("INT"); // Parse a record and keep the value only int value = h.parse<int>("INT"); // Parse a record if available, or get a fallback value auto record = h.parseOr<int>("INT", -1); // The above line is a shortcut for Record<int> record("INT", -1); if (h.has(record.keyword)) { record = h.parse<T>(record.keyword); } where h is a Header.