The Agena language

Overview

Agena offers various flow control facilities such as

if/then/elif/onsuccess/else conditions,
case of/onsuccess/else conditions similar to C's switch/case statements,
if operator to return alternative values,
numerical for/from/to/by loops where start, stop, and step values are optional, and automatic round-off error correction of iteration variables,
numerical for/from/downto/by loops where step values are optional,
combined numerical for/while loops,
for/in loops over strings and complex data structures,
while, do/as and do/until loops similar to Modula's while and repeat/until not() iterators,
a skip statement to prematurely trigger the next iteration of a loop,
a break statement to prematurely leave a loop,
a redo statement to restart the current iteration of a loop,
a relaunch stament to restart a loop from its beginng all over,
try/catch to handle exceptions.

available are:

rational and complex numbers, with extensions such as infinity and undefined,
strings,
Booleans such as true, false, and fail,
the null value meaning 'nothing',
multi-purpose tables implemented as associative arrays to hold any kind of data, taken from Lua,
Cantor sets as collections of unique items,
sequences, i.e. vectors, to internally store items in strict sequential order,
pairs to hold two values or pass arguments in any order to procedures,
registers, i.e. fixed-size vectors that can also conceil data through its pointer to the top,
user-defined types for sequences, tables, registers, and pairs to allow for special-purpose handling,
data type validation with the :: and :- operators and the optional double colon facility in parameter lists,
threads, userdata, and lightuserdata inherited from Lua,
multisets (bags), singly-, unrolled singly- and doubly-linked lists, heaps, bi-directional maps, and dual numbers.

For performance, basic operations on most of these types have been built into the Agena kernel.

with full lexical scoping are supported, as well, and provide the following extensions:

the << (args) -> expression >> syntax to easily define simple functions,
remember tables to conduct recursion at high speed and at low memory consumption, to remember already computed results, and to use predefined results,
user-defined types,
the nargs system variable which holds the number of arguments actually passed to a procedure,
metamethods originally inherited from Lua to define operations for tables, sets, sequences, registers, pairs, and userdata,
OOP-style methods for tables,
self-defined binary operators.

Some other functions are:

graphical capabilities for the Solaris, Mac OS X, Linux, and Windows versions,
an arbitrary precision mathematical library,
IPv4 network data transfer,
easy configuration of your personal environment via the Agena initialisation file,
an easy-to-use package system also providing a means to load a library and define short names for all package procedures at a stroke (with function),
enumeration and multiple assignments,
scope control via the scope/epocs keywords,
accessibility of the last iteration value of a loop control variable in the surrounding block,
functions to support fast text processing (see in, replace, lower, and upper operators, as well as the functions in the strings and utils packages),
the binio package to easily read and write files in binary mode,
facility to store any Agena data to a file and read it back later into a new session (save and read functions),
stack programming,
extended tests on data at function invocation and return,
undergraduate Calculus, Linear Algebra, and Statistics packages,
@ and $ for fast mapping and selection,
various bitwise operators,
direct access to the file system and the local network,
dBASE III/IV file support to exchange data with standard applications,
XML, CSV, INI, gzip, and tar file support,
full international code page support.