WHITESPACE = _{ WHITE_SPACE }
COMMENT = _{ "#" ~ (!NEWLINE ~ ANY)* }
DELIM = _{ &")" | &"}" | &"," | &WHITESPACE | &EOI }

operator = _{ "+" | "-" | "*" | "/" | "//" | "%" | "**" | "^" }
unicode_ident = _{ XID_START ~ XID_CONTINUE* }
ident = @{ unicode_ident | operator }

delimited_digits = _{ ( ASCII_DIGIT | "_" ~ &ASCII_DIGIT )* }
num = @{
    "-"? ~ ( "0" | '1'..'9' ~ delimited_digits )
    ~ ( "." ~ ASCII_DIGIT ~ delimited_digits )?
    ~ ( "E" ~ "-"? ~ ASCII_DIGIT ~ delimited_digits )?
}

raw_string_inner = { (!PEEK ~ ANY)* }
raw_string = @{ PUSH("'"+) ~ raw_string_inner ~ POP }

string_inner = { (!"\"" ~ ANY)* }
string = @{ "\"" ~ string_inner ~ "\""}

literal = { num | string | raw_string }

anon_exp = ${ literal | ident }

parens = { "(" ~ list ~ ")" }
block = { "{" ~ list ~ "}" }

apply = ${ anon_exp ~ parens }
block_apply = ${ anon_exp ~ block }
walk = { anon_exp ~ "." ~ ident }


pipe = { anon_exp ~ ( ">>" ~ anon_exp )*}
named_exp = { pipe ~ "->" ~ ident }

exp = { named_exp | pipe }

list = { ( exp ~ ","? )* }



file = { SOI ~ list ~ &EOI }