pipeline.ebnf

# Grammar for command pipeline.
# For our purposes it is enough to know boundaries of top-level commands
# in pipeline, their structure isn't interesting to us. However, in order
# to properly split pipeline it is needed to parse groups, strings, etc.

@no_skip_ws
Pipe = '|' !'|';

@export
Pipeline = first_command:TopLevelCommand { Pipe rest_commands:TopLevelCommand };

@position
TopLevelCommand = Command;

Command = {Segment};

Segment = @:Group | @:Subshell | @:String | @:Char;

Group = '{' Command '}';
Subshell = '(' Command ')';
String = SingleQuoteString | DoubleQuoteString;
Char = (!'|' char);

@no_skip_ws
DoubleQuoteString = '"' {('\\' char) | (!'"' char)} '"';

@no_skip_ws
SingleQuoteString = '\'' {!'\'' char} '\'';

@no_skip_ws
Whitespace = {' ' | '\t' | '\n' | '\r'};