GRL_Literals_en.md

Grule Rule Language (GRL) Literals

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String Literals

In GRL, a string is any sequence of characters surrounded by either a single ' or double " quotes. If the literal is started with single quote, then it must be terminated by single quote. The same for double quote.

For example

"a quick brown fox jumps over a lazy dog"

or

'a quick brown fox jumps over a lazy dog'

A string literal may contain white space characters such as space, tab or a carriage-return

For example

"A quick brown fox
    Jumps
Over a lazy dog"

To include special characters in string, you can escape them as is normal in Go

For example

"This string contains \" Double Quote"

Number Literals

GRL follows literal numbering as specified by the Golang specification as best as it can. It understands various numbers notation such as Base10 (Decimals), Base8 (Octal) and Base16 (Hex). Base2 (Binary) is not yet implemented.

Integer Literal

Decimals

In Base 10 - For Example

0
123
34592
-1
-47234

In Base 8 - For Example

01
07
010
017
-034
-045
04328 (error : invalid octal number)

In Base 16 - For Example

0x1
0xF
0x10
0x1F
0xFF00
-0x12
-0x00ABCD
-0x890AbCdEf

Real Numbers / Float Literals

In Base 10 - For Example

0.
72.40
072.40
2.71828
1.e+0
6.67428e-11
1E6
.25
.12345E+5
-072.40
-2.71828
-1.e+0

In Base 16 - For Example

0x1p-2 
0x2.p10
0x1.Fp+0
0X.8p-0
0X_1FFFP-16
0x15e-2

Boolean Literal

true
TRUE
True
TrUe
false
False
FALSE
FaLsE