Function parse 

pub fn parse(input: &str) -> Result<Program, ParseError>

Parse a slash-command string into a Program AST.

Grammar (informally)

program  := pipeline ( ( '&&' | '||' ) pipeline )*
pipeline := command  ( ( '|'  | '|&' ) command  )* redirect?
redirect := ( '>' | '>>' ) filename
command  := SLASH_TOKEN arg*

Tokenization splits on ASCII whitespace only — no quoting, no escaping.

Priority inference

Priority is inferred from the raw command token’s casing before normalization:

Shape	Priority
ALL_CAPS	Max
TitleCase	High
camelCase	Medium
kebab-case	Low
snake_case	Lowest

Errors

Returns ParseError on any structural violation, including:

• Two commands in sequence without an operator
• Standalone !/!!/!!! urgency tokens
• More than three ! markers on a command
• Double ?? optional suffix
• Malformed builder chain (unmatched parentheses)
• Redirection followed by a non-&&/|| token
• Digits in command names outside the /test-family

Examples

use slash_lang::parser::parse;
use slash_lang::parser::ast::{Priority, Urgency};

let program = parse("/Build.target(release)! | /test").unwrap();
let cmd = &program.pipelines[0].commands[0];
assert_eq!(cmd.name, "build");
assert_eq!(cmd.priority, Priority::High);
assert_eq!(cmd.urgency, Urgency::Low);
assert_eq!(cmd.args[0].name, "target");
assert_eq!(cmd.args[0].value.as_deref(), Some("release"));