| Commands <- Spacing Sequence? EOF |
| Sequence <- Spacing Pipeline CommandSpacing ((EndOfLine|Colon) Spacing Pipeline CommandSpacing)* CommandSpacing (EndOfLine|Colon)? Spacing |
| Pipeline <- Command (Spacing Pipe Spacing Command?)* |
| Command <- CommandName (ParameterDelim Parameter | &(CommandSpacing? EndOfLine CommandSpacing? (String | Number | DollarIdentifier | ParameterName | CurlyExpression | Substitution)) CommandSpacing? EndOfLine CommandSpacing? Parameter)* |
| CommandName <- DollarIdentifier | Identifier |
| Parameter <- ParameterName (ParameterDelim ParameterValue)? | ParameterValue |
| ParameterName <- "-" "-"? Identifier? |
| ParameterValue <- DollarIdentifier | Identifier | Number | String | CurlyExpression | Substitution |
| Substitution <- LBrack Spacing Pipeline? Spacing RBrack |
| CurlyExpression <- LCurly (CurlyExpression | !RCurly .)* Spacing RCurly |
| Identifier <- "[a-zA-Z_]([a-zA-Z_0-9]|-)*" |
| DollarIdentifier <- "\$" Identifier? |
| Number <- "[0-9]+" |
| String <- StringRun (Spacing "\+" Spacing StringRun)* |
| Colon <- ";" |
| Pipe <- "\|" |
| LCurly <- "\{" |
| RCurly <- "\}" |
| LBrack <- "\[" |
| RBrack <- "\]" |
| Spacing <- ("[ \t\n\r]+" | SlComment | MlComment)* |
| ParameterDelim <- "[ \t]+" |
| CommandSpacing <- ("[ \t]+" | SlComment | MlComment)* |
| EndOfLine <- "[\n\r]+" |
| SlComment <- '//[^\n\r]*' |
| MlComment <- '(?m)(?s)/\*.*\*/' |
| StringRun <- "'" (Escape | !"['\\]" .)* "'" | '"' (Escape | !'["\\]' .)* '"' |
| Escape <- "\\" "[btnfr\"'\\]" |
