.. index:: single: Data Type; Introduction ============================== Check Data Type and Conversion ============================== In this chapter we are going to learn about the functions that can be used for * Checking Data Type * Checking Character * Conversion .. index:: pair: Data Type; Check Data Type Check Data Type =============== The next functions can be used to check the data type * isstring() * isnumber() * islist() * type() * isnull() .. index:: pair: Data Type; IsString() IsString() Function =================== Using the IsString() function we can know if the value is a string or not Syntax: .. code-block:: ring IsString(value) ---> 1 if the value is a string or 0 if not Example: .. code-block:: ring see isstring(5) + nl + # print 0 isstring("hello") + nl # print 1 .. index:: pair: Data Type; IsNumber() IsNumber() Function =================== Using the IsNumber() function we can know if the value is a number or not Syntax: .. code-block:: ring IsNumber(value) ---> 1 if the value is a number or 0 if not Example: .. code-block:: ring see isnumber(5) + nl + # print 1 isnumber("hello") + nl # print 0 .. index:: pair: Data Type; IsList() IsList() Function =================== Using the IsList() function we can know if the value is a list or not Syntax: .. code-block:: ring IsList(value) ---> 1 if the value is a list or 0 if not Example: .. code-block:: ring see islist(5) + nl + # print 0 islist("hello") + nl + # print 0 islist([1,3,5]) # print 1 .. index:: pair: Data Type; Type() Type() Function =============== We can know the type of a value using the Type() Function. Syntax: .. code-block:: ring Type(value) ---> The Type as String Example: .. code-block:: ring see Type(5) + nl + # print NUMBER Type("hello") + nl + # print STRING Type([1,3,5]) # print LIST .. index:: pair: Data Type; IsNULL() IsNULL() Function ================= We can check the value to know if it's null or not using the IsNULL() function Syntax: .. code-block:: ring IsNULL(value) ---> 1 if the value is NULL or 0 if not Example: .. code-block:: ring see isnull(5) + nl + # print 0 isnull("hello") + nl + # print 0 isnull([1,3,5]) + nl + # print 0 isnull("") + nl + # print 1 isnull("NULL") # print 1 .. index:: pair: Data Type; Check Character Check Character =============== The next functions can be used to check character * isalnum() * isalpha() * iscntrl() * isdigit() * isgraph() * islower() * isprint() * ispunct() * isspace() * isupper() * isxdigit() .. index:: pair: Data Type; IsAlNum() IsAlNum() Function ================== We can test a character or a string using the IsAlNum() Function Syntax: .. code-block:: ring IsAlNum(value) ---> 1 if the value is digit/letter or 0 if not Example: .. code-block:: ring see isalnum("Hello") + nl + # print 1 isalnum("123456") + nl + # print 1 isalnum("ABCabc123") + nl + # print 1 isalnum("How are you") # print 0 because of spaces .. index:: pair: Data Type; IsAlpha() IsAlpha() Function ================== We can test a character or a string using the IsAlpha() Function Syntax: .. code-block:: ring IsAlpha(value) ---> 1 if the value is a letter or 0 if not Example: .. code-block:: ring see isalpha("Hello") + nl + # print 1 isalpha("123456") + nl + # print 0 isalpha("ABCabc123") + nl + # print 0 isalpha("How are you") # print 0 .. index:: pair: Data Type; IsCntrl() IsCntrl() Function ================== We can test a character or a string using the IsCntrl() Function Syntax: .. code-block:: ring IsCntrl(value) ---> 1 if the value is a control character (no printing position) or 0 if not Example: .. code-block:: ring See iscntrl("hello") + nl + # print 0 iscntrl(nl) # print 1 .. index:: pair: Data Type; IsDigit() IsDigit() Function ================== We can test a character or a string using the IsDigit() Function Syntax: .. code-block:: ring IsDigit(value) ---> 1 if the value is a digit or 0 if not Example: .. code-block:: ring see isdigit("0123456789") + nl + # print 1 isdigit("0123a") # print 0 .. index:: pair: Data Type; IsGraph() IsGraph() Function ================== We can test a character or a string using the IsGraph() Function Syntax: .. code-block:: ring IsGraph(value) ---> 1 if the value can be printed (Except space) or 0 if not Example: .. code-block:: ring see isgraph("abcdef") + nl + # print 1 isgraph("abc def") # print 0 .. index:: pair: Data Type; IsLower() IsLower() Function ================== We can test a character or a string using the IsLower() Function Syntax: .. code-block:: ring IsLower(value) ---> 1 if the value is lowercase letter or 0 if not Example: .. code-block:: ring see islower("abcDEF") + nl + # print 0 islower("ghi") # print 1 .. index:: pair: Data Type; IsPrint() IsPrint() Function ================== We can test a character or a string using the IsPrint() Function Syntax: .. code-block:: ring IsPrint(value) ---> 1 if the value occupies a printing position or 0 if not Example: .. code-block:: ring see isprint("Hello") + nl + # print 1 isprint("Nice to see you") + nl + # print 1 isprint(nl) # print 0 .. index:: pair: Data Type; IsPunct() IsPunct() Function ================== We can test a character or a string using the IsPunct() Function Syntax: .. code-block:: ring IsPunct(value) ---> 1 if the value is a punctuation character or 0 if not Example: .. code-block:: ring see ispunct("hello") + nl + # print 0 ispunct(",") # print 1 .. index:: pair: Data Type; IsSpace() IsSpace() Function ================== We can test a character or a string using the IsSpace() Function Syntax: .. code-block:: ring IsSpace(value) ---> 1 if the value is a white-space or 0 if not Example: .. code-block:: ring see isspace(" ") + nl + # print 1 isspace("test") # print 0 .. index:: pair: Data Type; IsUpper() IsUpper() Function ================== We can test a character or a string using the IsUpper() Function Syntax: .. code-block:: ring IsUpper(value) ---> 1 if the value is an uppercase alphabetic letter or 0 if not Example: .. code-block:: ring see isupper("welcome") + nl + # print 0 isupper("WELCOME") # print 1 .. index:: pair: Data Type; IsXdigit() IsXdigit() Function =================== We can test a character or a string using the IsXdigit() Function Syntax: .. code-block:: ring IsXdigit(value) ---> 1 if the value is a hexdecimal digit character or 0 if not Example: .. code-block:: ring see isxdigit("0123456789abcdef") + nl + # print 1 isxdigit("123z") # print 0 .. index:: pair: Data Type; Conversion Conversion ========== The next functions can be used for conversion * number() * string() * ascii() * char() * hex() * dec() * str2hex() * hex2str() .. index:: pair: Data Type; Number() Number() Function ================= We can convert strings to numbers using the Number() function or the + operator. Syntax: .. code-block:: ring Number(string) ---> Number 0 + string ---> Number Example: .. code-block:: ring see number("5") + 5 + nl # print 10 see 0 + "10" + 2 # print 12 .. index:: pair: Data Type; String() String() Function ================= We can convert numbers to strings using the String() function or the + operator. Syntax: .. code-block:: ring String(number) ---> String "" + number ---> String Example: .. code-block:: ring see string(5) + 5 + nl # print 55 see "" + 10 + 2 # print 102 .. index:: pair: Data Type; Ascii() Ascii() Function ================ We can get the ASCII code for a letter using the Ascii() function Syntax: .. code-block:: ring Ascii(character) ---> ASCII Code Example: .. code-block:: ring See ascii("m") + nl + # print 109 ascii("M") # print 77 .. index:: pair: Data Type; Char() Char() Function =============== We can convert the ASCII code to character using the Char() function. Syntax: .. code-block:: ring Char(ASCII Code) ---> character Example: .. code-block:: ring See char(109) + nl + # print m char(77) # print M .. index:: pair: Data Type; Hex() Hex() Function ============== We can convert decimal to hexadecimal using the Hex() function. Syntax: .. code-block:: ring Hex(decimal) ---> hexadecimal Example: .. code-block:: ring See hex(10) + nl + # print a hex(200) # print c8 .. index:: pair: Data Type; Dec() Dec() Function ============== We can convert hexadecimal to decimal using the Dec() function Syntax: .. code-block:: ring Dec(hexadecimal) ---> decimal Example: .. code-block:: ring See dec("a") + nl + # print 10 dec("c8") # print 200 .. index:: pair: Data Type; Str2Hex() Str2hex() Function ================== We can convert string characters to hexadecimal characters using the Str2hex() function. Syntax: .. code-block:: ring Str2hex(string) ---> hexadecimal string Example: .. code-block:: ring See str2hex("hello") # print 68656c6c6f .. index:: pair: Data Type; Hex2str() Hex2str() Function ================== We can convert hexadecimal characters to string using the Hex2str() function Syntax: .. code-block:: ring Hex2Str(Hexadecimal string) ---> string Example: .. code-block:: ring See hex2str("68656c6c6f") # print hello