has parse parse_all parse_n parse_n parse_n_or parse_n_or parse_or parse_or parse_struct parse_struct_or parse_struct_or parseAll parseOr parseSeq parseSeqOr parseStruct parseStructOr read_all read_all_keywords read_all_keywords_values readAll readKeywords readKeywordsValues remove write write write_comment write_history write_n write_n write_n_in write_n_in writeComment writeHistory writeSeq writeSeqIn

parse_or() [2/2] Record< T > parse_or ( const std::string &  keyword, T  fallback_value, const std::string &  fallback_unit = "", const std::string &  fallback_comment = ""  ) 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.parse_or<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.