bareword_char      = @{ !("|" | ";" | "\"" | "'" | WHITESPACE | COMMENT) ~ ANY }
single_string_char = @{ "\\'" | (!"'" ~ ANY) }
double_string_char = @{ "\\\"" | (!"\"" ~ ANY) }

bareword      = @{ bareword_char+ }
single_string = @{ single_string_char+ }
double_string = @{ double_string_char+ }

word     = ${
    bareword |
    "'" ~ single_string ~ "'" |
    "\"" ~ double_string ~ "\""
}

exe      = { word+ }
pipeline = { exe ~ ("|" ~ exe)* }
commands = { pipeline ~ (";" ~ pipeline)* }

line = { SOI ~ commands ~ EOI }

WHITESPACE = _{ (" " | "\t" | "\n") }
COMMENT    = _{ "#" ~ ANY* }