Scriptol, for robotics and apps built on Web standards
The Scriptol language created in 2001 by Denis Sureau was defined according to seven rules: simplicity, security, conformance
to standards, objectivity, multiple orientations, portability, easy
Control structures are different and more powerful than in classical languages, allowing pattern-matching and automata (DFA). Security is one main goal of the language and variables are typed.
It is an universal language for robotics, making dynamic web pages, scripting, prototyping or HTML 5 based applications. It allows to integrate XML in source code.
Several innovations in Scriptol have been adopted by other languages created since 2001. It is the first language to have reactive variables, thus combining reactive and imperative programming.
You may use Scriptol:
- For web pages programming: Scriptol may be compiled into PHP, thus it is portable. The compiler detects errors before running the program.
- For script writing: This a clear and powerful language, very intuitive.
- For prototyping: test a scriptol program with the interpreter and produce a C++ source for inclusion into a large project.
- To make intelligent robots.
Features of Scriptol
- Universal: suited for applications, scripts or web pages.
- Typed variables.
- Object oriented. Even primitives and constants have methods.
- XML oriented: it is a data structure of the language.
- Control structures are safe while .. let, for .. in, etc...
- Pattern-matching and automata easy with the do..case structure.
- Rules are easily implemented thanks to the composite if structure.
- Multiple assignments. A function can return several values.
- Indexed or associative arrays.
- Reactive programming. Scriptol has reactive variable you can mix with imperative code.
Statements are terminated by end of line.
Xml-like terminators: /if, /while, etc...
Each operator has only one usage, not several acccording the context as in C.
Scalar types are those of the real life: text, number, real, etc...
Compound assignments have the form:
x + 1 // means for: x = x + 1
Scalars, xml, class.
- if ... else, composite if
- for ... in ... step
- while ... let
- do case ... while, do case ... until
- break, continue, return
You can mix different types of comparisons and compare different types of data from one test to another.
if a = 10: print "equal" < 10: print "less" else print "more" /if
The while structure has several form and the let terminator protects against infinite loops.
while x < 10 print x /while // infinite loop
while x < 10 print x let x + 1
The header is similar to that of C but several types may be returned together. The terminator is the return statement, the keyword only if the function returns nothing.
int, text funcname(... arguments...) ...statements... return a, b
Simple print command:
The print command sends a newline after the text. The echo command does not.
print "Hello world!"
The contents of two lists are added and printed.
var list1=[1,2,3] var list2=[10,20,30] for i, v in list1 print v + list2[i] /for
Should print: 11 22 33.
Embedding code into HTML page:
The scriptol code is converted to PHP by the solp compiler.
<?sol print "code embedded inside html"; ?>
Using reactive variables
This allows programming by formulas without having to write the code update the variables.
react sum = v1 + v2
sum.output = 'document.getElementById("sum").value = this.value;'
The v1 and v2 variables are assigned through the HTML interface. The HTML element with id "sum" will be updated whenever the contents of the variables v1 and v2 will be changed.
The syntax is closer to the standard that is developed over time, where or a different syntax has no interest in itself:
- Dyn is replaced by var.
- Methods of array and dictionary and builtin functions have evolved to distance themselves from PHP.
Scriptol 2 requires editing of existing programs by simple substitutions without grammatical change.