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To use SIL like any other scripting language follow a few simple syntax rules.

General rules

  • All instructions end with a semicolon ;
  • Comments are introduced using //comment_until_end_of_line or /* comment */
Example
// single line comment
/*
this comment
spans over
multiple lines
*/ 

Types

Basic Types

SIL defines the following base types:

  • string - defines a string, example literal is "abc"
  • boolean - defines boolean values true and false
  • number - any numeric value
  • integer - a numeric value without a fractional component
  • byte - a byte
  • date - a date, like "2010-03-30"
  • interval - a time interval, like "2d 3h"

Important notes

  • interval - data type does not represent the working interval (i.e. 8h), but the full interval. When we created SIL™ we thought about if we should introduce a working interval type (i.e. 8h / day) but this would have certain undesired implications (how long is your workday? in France, for instance, Friday is only 6h). With our custom fields, it's a matter of interpretation of the interval, and we have routines to help you transform a 24h interval to a working interval, or you can simply write your own.
  • date - data type can be used to represent dates and date-times.
  • number - data type internal storage is represented only by real numbers (double). However, the language accepts for historical reasons type declarations as "real", "double", "float" (treating them as "number", of course).
  • integer (or int) - is actually a long in the traditional sense

Arrays

Multi-value (arrays) types are also supported and composed of the base type followed by the array symbols [ ]  for each dimension of the array type. This translates to the following being valid array types:

  • string[]
  • boolean[]
  • number[][]
  • integer[]
  • date[][][]
  • interval[]
  • Person[][] - where Person is a user-defined structure

Key-Value Arrays (Maps)

Arrays are actually maps where values are keyed by their position in the list, and so key-value arrays are declared the same as regular arrays.

Learn more about maps and the indexing operator.

Structures

The general syntax for defining a structure is:

struct <name> {
	<type> <fieldName>;
}

Structures are defined by their name and pairs of field type and field name. A structure can have any number of fields. The type of each field can be a simple type, a user-defined structure (including the structure being defined) or arrays of these types.

Example:

struct Person {
	string id;
	string name;
	date birthDate;
	Person manager;
	Person [] subordinates;
}

To access the value of a field from a variable the syntax will look like:

<varName>.<fieldName>

Initializing Structures:

Example 1
// considering structure Person defined above
Person p; 
p.name = "John Doe";
p.id = "1234567";
string hisManager = p.manager.name;
string employee = p.subordinates[0].name;
Example 2
struct P {
    int x;
    int y;
    int z;
}

struct S {
  string a;
  number b;
  date c;
  P point;
};

S s = {"-text-", 3.14, "1974-03-15", {0, 1, 2}}; //one line init
//you do not have to expand the creation of the struct anymore
//you do not need to quote them as strings

Constants

This topic is about constant values, NOT about the read-only attribute of variables.

Single Value Constants

For numbers, integers and boolean values, constants are represented without any additional alterations.

Example
integer n = 1;
number pi = 3.14;
boolean iLikeSIL = true; 
//bytes need explicit casts. since the literal is an integer
byte b = (byte) 20;

Constants for string, date and interval are provided between double quotes (").

    • The full format for date is "yyyy-MM-ddTHH:mm:ss.SSSZ", and may include the time-zone information at the end. The short format "yyyy-MM-dd" is accepted as well.
    • The intervals should be provided in the JIRA standard format: "1w 2d 3h 4m".
Example
// valid dates
"2010-12-31"
"2010-12-31T24:59:59" (the default configured timezone is taken)
"2010-12-31T24:59:59Z" (Zulu time = UTC = GMT)
"2010-12-31T22:59:59+0200" (UTC+2)
"2010-12-31T24:59:59.999Z" (Zulu time = UTC = GMT)
"2010-12-31T22:59:59.999+0200" (UTC+2)

// interval
"1w 2d 3h 4m"

Array Constants

Arrays are created using the following syntax:

{<value1>, <value2>, ..., <value3>}
Example
{"this", "is", "a", "string", "array"} // string array
{{0,1}, {2,3}, {4,5}} // number matrix
{true, false, false} // boolean array
{"1d", "2d", "3d"} // interval array
{ variable1, variable2, variable3 } // array of the type of variable#, where variable# can also be an array

Note

We currently do not support constant representation of key-value arrays. You will need to build one using the indexing operator.

Variable Declaration

The general syntax for declaring a variable is: 

<type> varname; // declaration without initialization
// or
<type> varname = <expression>; // declaration with initialization

 

Example
string name = "John Doe";
integer random = 2;
number pi = 3.14;
boolean valid;
date today = currentDate();
interval spent = "1h 30m";
interval estimate = "2d" - spent;
number [][] matrix = {{0,1}, {2,3}, {4,5}};

Constant variables

Variables can be made read-only by adding the keyword "const" before the type when the variable is first defined.

const string COMMA = ",";
const number PI = 3.14;

If set to an array or structure, the read-only attribute will be applied to all the elements of the array or fields of the structure.

Routine Declaration

In addition to the routines provided out-of-the-box by SIL, you can define your local routines (user-defined routines or UDRs in short) that use the following syntax:

function <name>(<type> param1, <type> param2, ...) {
   Instruction1;
   ...
   InstructionN;
   return <value>;
}

Learn more about UDRs.

Explicit Type Casts

Most of the time, SIL™ will attempt to do the type-casting for you automatically, however this cannot be always performed like this. These type casts allow you explicitly to convert a variable to a specific type.The general syntax for casting is:

(<target_type>)varname
Example
integer n = 1;
number x = 3.14;
string s = "2";
return n + s; // what will this return? 3 or "12"?
return (string)n + s; // now we know that adding 2 strings will result in "12"
return n + (number)s; // adding 2 numbers will definitely return a number (3)

Note

Not all type casts are valid. For example it makes no sense to convert an interval to a date.

See also

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