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Euphoria – Library Routines ”; Previous Next A large number of library routines are provided. Some are built right into the interpreter, ex.exe, exw.exe or exu. Others are written in Euphoria and you must include one of the .e files in euphoriainclude directory to use them. To indicate what kind of object may be passed in and returned, the following prefixes are used − S.No Prefix & Description 1 x a general object (atom or sequence) 2 s a sequence 3 a an atom 4 i an integer 5 fn an integer used as a file number 6 st a string sequence, or single-character atom Predefined Types As well as declaring variables with these types, you can also call them just like ordinary functions, in order to test if a value is a certain type. integer − test if an object is an integer atom − test if an object is an atom sequence − test if an object is a sequence object − test if an object is an object (always true) Sequence Manipulation length − return the length of a sequence repeat − repeat an object n times to form a sequence of length n reverse − reverse a sequence append − add a new element to the end of a sequence prepend − add a new element to the beginning of a sequence Searching and Sorting compare − compare two objects equal − test if two objects are identical find − find an object in a sequence – start searching from element number 1 find_from − find an object in a sequence – start searching from any element number match − find a sequence as a slice of another sequence – start searching from element number 1 match_from − find a sequence as a slice of another sequence – start searching from any element number sort − sort the elements of a sequence into ascending order custom_sort − sort the elements of a sequence based on a compare function that you supply Pattern Matching lower − convert an atom or sequence to lower case upper − convert an atom or sequence to upper case wildcard_match − match a pattern containing ? and * wildcards wildcard_file − match a file name against a wildcard specification Math These routines can be applied to individual atoms or to sequences of values. sqrt − calculate the square root of an object rand − generate random numbers sin − calculate the sine of an angle arcsin − calculate the angle with a given sine cos − calculate the cosine of an angle arccos − calculate the angle with a given cosine tan − calculate the tangent of an angle arctan − calculate the arc tangent of a number log − calculate the natural logarithm floor − round down to the nearest integer remainder − calculate the remainder when a number is divided by another power − calculate a number raised to a power PI − the mathematical value PI (3.14159…) Bitwise Logical Operations These routines treat numbers as collections of binary bits, and logical operations are performed on corresponding bits in the binary representation of the numbers. There are no routines for shifting bits left or right, but you can achieve the same effect by multiplying or dividing by powers of 2. and_bits − perform logical AND on corresponding bits or_bits − perform logical OR on corresponding bits xor_bits − perform logical XOR on corresponding bits not_bits − perform logical NOT on all bits File and Device I/O To do input or output on a file or device you must first open the file or device, then use the routines below to read or write to it, then close the file or device. open() will give you a file number to use as the first argument of the other I/O routines. Certain files/devices are opened for you automatically (as text files) − 0 – standard input 1 – standard output 2 – standard error open − open a file or device close − close a file or device flush − flush out buffered data to a file or device lock_file − lock a file or device unlock_file − unlock a file or device print − print a Euphoria object on one line, with braces and commas {,,} to show the structure pretty_print − print a Euphoria object in a nice readable form, using multiple lines and appropriate indentation ? x − shorthand for print(1, x) sprint − return a printed Euphoria object as a string sequence printf − formatted print to a file or device sprintf − formatted print returned as a string sequence puts − output a string sequence to a file or device getc − read the next character from a file or device gets − read the next line from a file or device get_bytes − read the next n bytes from a file or device prompt_string − prompt the user to enter a string get_key − check for key pressed by the user, don”t wait wait_key − wait for user to press a key get − read the representation of any Euphoria object from a file prompt_number − prompt the user to enter a number value − read the representation of any Euphoria object from a string seek − move to any byte position within an open file where − report the current byte position in an open file current_dir − return the name of the current directory chdir − change to a new current directory dir − return complete info on all files in a directory walk_dir − recursively walk through all files in a directory allow_break − allow control-c/control-Break to terminate your program or not check_break − check if user has pressed control-c or control-Break Mouse Support (DOS32 and Linux) On Windows XP, if you want the DOS mouse to work in a (non-full-screen) window, you must disable QuickEdit mode in the Properties for the DOS Window. get_mouse − return mouse “events”