9223372036854775807įree Pascal does automatic type conversion in expressions where different kinds of integer types are used. Var Age, Year, Grade : integer Circumference : real LetterGrade : char DidYouFail : boolean For example, the following pieces of code are equivalent: Free Pascal supports initializing of PChar typed constants, or a direct assignment. a variable of type PChar is a pointer that points to an array of type Char, which is ended by a null-character (#0). The PChar type can be understood best as the Pascal equivalent of a C-style null-terminated string, i.e. PChar is defined as a pointer to a Char type, but allows additional operations. Free Pascal supports the Delphi implementation of the PChar data type.Note: some Unicode characters require two WideChars. The WideChar is a two-byte character (an element of a DBCS: Double Byte Character Set) and can hold a Unicode character.Be sure to enclose them in single quotes, like so: 'a' 'B' '+' Standard Pascal uses 8-bit characters, not 16-bits, so Unicode, which is used to represent all the world's language sets in one UNIfied CODE system, is not supported. In Pascal, you can express real values in your code in either fixed-point notation or in scientific notation, with the character E separating the mantissa from the exponent. Real values are stored inside the computer similarly to scientific notation, with a mantissa and exponent, with some complications. The Real data type has a range from 3.4x10 -38 to 3.4x10 38, in addition to the same range on the negative side.The Word data type is a 16-bit unsigned integer, which has a range of 0 to 65535.For backward compatibility purposes, a 32-bit signed integer is a longint and can hold a much greater range of values, 2147483647 to -2147483648. This is the signed range that can be stored in a 16-bit word, and is a legacy of the era when 16-bit CPUs were common. On PCs before the 80386, "integer" meant 16-bit whole numbers in the range from -32768 to 32767. the size of an integer depends on the compiler and the processor. The Integer data type can contain whole numbers.Experienced Pascal programmers also use pointers for dynamic memory allocation, objects for object-oriented programming, and many others, but this gets you started. Standard Pascal does not make provision for the string data type, but most modern compilers do. The basic data field data types in Pascal include: All identifiers in the list are declared as being of the same data type. IdentifierList is a series of identifiers, separated by commas ( ,). Var IdentifierList1 : DataType1 IdentifierList2 : DataType2 IdentifierList3 : DataType3.
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