$Variable Sigil
$Variable
Sigil
Expand values as a scalar
Description
The scalar token is used to tell Murex to expand variables and sub-shells as a string (ie one single parameter) irrespective of the data that is stored in the string. One handy common use case is file names where traditional POSIX shells would treat spaces as a new file, whereas Murex treats spaces as a printable character unless explicitly told to do otherwise.
The string token must be followed with one of the following characters: alpha, numeric, underscore (_
) or a full stop / period (.
).
Examples
ASCII variable names
» $example = "foobar"
» out $example
foobar
Unicode variable names
Variable names can be non-ASCII however they have to be surrounded by parenthesis. eg
» $(比如) = "举手之劳就可以使办公室更加环保,比如,使用再生纸。"
» out $(比如)
举手之劳就可以使办公室更加环保,比如,使用再生纸。
Infixing inside text
Sometimes you need to denote the end of a variable and have text follow on:
» $partial_word = "orl"
» out "Hello w$(partial_word)d!"
Hello world!
Variables are tokens
Please note the new line (\n
) character. This is not split using $
:
» $example = "foo\nbar"
Output as a scalar ($
):
» out $example
foo
bar
Output as an array (@
):
» out @example
foo bar
Scalar and Array Sub-shells
Scalar:
» out ${ %[Mon..Fri] }
["Mon","Tue","Wed","Thu","Fri"]
Array:
» out @{ %[Mon..Fri] }
Mon Tue Wed Thu Fri
out
will take an array and output each element, space delimited. Exactly the same howecho
would in Bash.
Variable as a Command
If a variable is used as a commend then Murex will just print the content of that variable.
» $example = "Hello World!"
» $example
Hello World!
Detail
Infixing
Strings and sub-shells can be expanded inside double quotes, brace quotes as well as used as barewords. But they cannot be expanded inside single quotes.
» set example="World!"
» out Hello $example
Hello World!
» out 'Hello $example'
Hello $example
» out "Hello $example"
Hello World!
» out %(Hello $example)
Hello World!
However you cannot expand arrays (@
) inside any form of quotation since it wouldn't be clear how that value should be expanded relative to the other values inside the quote. This is why array and object builders (%[]
and %{}
respectively) support array variables but string builders (%()
) do not.
See Also
- Reserved Variables: Special variables reserved by Murex
"Double Quote"
: Initiates or terminates a string (variables expanded)%(Brace Quote)
: Initiates or terminates a string (variables expanded)'Single Quote'
: Initiates or terminates a string (variables not expanded)(brace quote)
: Write a string to the stdout without new line (deprecated)@Array
Sigil: Expand values as an arrayja
(mkarray): A sophisticated yet simply way to build a JSON arraylet
: Evaluate a mathematical function and assign to variable (deprecated)out
: Print a string to the stdout with a trailing new line characterset
: Define a local variable and set it's value~
Home Sigil: Home directory path variable
This document was generated from gen/parser/variables_doc.yaml.