Input syntax

Lanat follows the syntax you would expect from a command-line interface, while also expanding it with some other features. A user that is familiar with other command-line programs will have no trouble using a program built with Lanat.

Let's take a deep dive into the syntax Lanat expects to parse.

Arguments

To refer to an argument, the syntax is: (Spaces shall not be present in the actual input)

prefix [prefix] name

The name must be any of the names defined in the argument.
The prefix must be a single character matching the prefix of the argument.

Argument name lists

You can refer to multiple arguments at once by listing their names after a single prefix with the following syntax: (Spaces shall not be present in the actual input)

prefix n1 [n2 ...]

nX must be any of the single character names defined in the argument.
The prefix must be a single character matching any of the prefixes of any of the arguments specified in the list, or either - or /.

Argument values

After specifying an argument, you can provide a value to it by using the syntax:

argument [ = ] value

When the = is present, no spaces should be present between these tokens.
value is:
[ tuple_start ] str1 [ str2... ] [ tuple_end ]
- tuple_[start|end] are the characters that define the start and end of a tuple. They are defined by TupleChar#current.
- strX is a string containing a value to be forwarded to the argument type.

Examples

Argument with value:
--name 12
Expanded into:
- Argument name:
  - Value: 12
  - Prefix: -
Argument name list:
-axvz 56
Expanded into:
- Arguments: a, x, v, z
- Value (for z): 56
- Prefix: -
Multiple arguments with multiple values:
/values 12 13 14 +t56
Expanded into:
- Argument values:
  - Values: 12, 13, 14
  - Prefix: /
- Argument t:
  - Value: 56
  - Prefix: +
Value with tuple:
--users ["Alice" "Bob" "Charlie"] /t=[1]
Expanded into:
- Argument users:
  - Value: {"Alice", "Bob", "Charlie"}
  - Prefix: -
- Argument t:
  - Value: 1
  - Prefix: /

Forward value

In some cases it may be useful to allow the user to provide a generic value to the program without specifying an argument. This is called a forward value. The syntax is (including the space):

-- value

value is a string containing anything. Lanat will not attempt to parse this.

Example

Simple program that would run another program (grep) with some provided arguments forwarded to it:
$ run-with --cmd "grep" -- -r "pattern" "file.txt"
Expanded into:
- Argument cmd:
  - Value: grep
  - Prefix: -
- Forward value: -r "pattern" "file.txt"

Last modified: 03 October 2024