Language Character Set

Object Pascal uses the ASCII character set, including a-Z, a-Z, 0-9, and other standard characters. Letters are case-insensitive. special single character symbols: # $ & '() * + ,-. /:; @ [] ^ {} combination of special characters :(**)(..).. //: = where: '[]' is equivalent '(..) ';' (**) 'is equivalent '{}'! "%? \ _ | ~ It is not a special symbol. It is used to give constants, variables, fields, types, attributes, processes, functions,ProgramUnit, library, and package. the identifier must start with _ or a letter. It can be followed by letters, numbers, and underscores, but cannot contain spaces. Although the length is arbitrary, it is only valid for the first 255 characters. Keywords cannot be identifiers. the number can be expressed in decimal format. There cannot be any space or comma in the middle, and there can be a "+ or-" prefix, not a positive. $ the number with the prefix is in hexadecimal format, for example, $ 8f.