From aac3549a72663c523a456b2f5d7c3b77f509cdd6 Mon Sep 17 00:00:00 2001 From: Greg Brown Date: Thu, 14 Jan 2021 11:42:55 +0000 Subject: Add labelled expressions. Restructure project (again). Convert `Cat` and `Alt` from binary to n+2-ary. --- autochomp/src/nibble.rs | 71 +++++++++++++++++++++++++++---------------------- 1 file changed, 39 insertions(+), 32 deletions(-) (limited to 'autochomp') diff --git a/autochomp/src/nibble.rs b/autochomp/src/nibble.rs index f6629f2..657a20f 100644 --- a/autochomp/src/nibble.rs +++ b/autochomp/src/nibble.rs @@ -1,8 +1,8 @@ chomp_macro::nibble! { - let opt(x) = _ | x; - let plus(x) = [plus](x . opt(plus)); + let opt(x) = _ : None | x : Some; + let plus(x) = [plus]((x : First) . (opt(plus) : Next)); let star(x) = opt(plus(x)); - let star_(base, step) = [rec](base | step . rec); + let star_(base, step) = [rec](base : Base | step . rec : Step); let Pattern_Whitespace = "\t"|"\n"|"\x0B"|"\x0c"|"\r"|" "|"\u{85}"|"\u{200e}"|"\u{200f}"|"\u{2028}"|"\u{2029}"; @@ -25,46 +25,53 @@ chomp_macro::nibble! { XID_Start | "_" | "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" ; let literal_char = - " " | "!" | "#" | "$" | "%" | "&" | "'" | - "(" | ")" | "*" | "+" | "," | "-" | "." | "/" | - "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | - "8" | "9" | ":" | ";" | "<" | "=" | ">" | "?" | - "@" | "A" | "B" | "C" | "D" | "E" | "F" | "G" | - "H" | "I" | "J" | "K" | "L" | "M" | "N" | "O" | - "P" | "Q" | "R" | "S" | "T" | "U" | "V" | "W" | - "X" | "Y" | "Z" | "[" | "]" | "^" | "_" | - "`" | "a" | "b" | "c" | "d" | "e" | "f" | "g" | - "h" | "i" | "j" | "k" | "l" | "m" | "n" | "o" | - "p" | "q" | "r" | "s" | "t" | "u" | "v" | "w" | - "x" | "y" | "z" | "{" | "|" | "}" | "~" | - "\\" . ("\"" | "'" | "n" | "r" | "t" | "\\" | "0" | - "x" . oct_digit . hex_digit | - "u{" . hex_digit . opt(hex_digit . opt(hex_digit . opt(hex_digit . opt(hex_digit . opt(hex_digit))))) . "}"); + (" " | "!" | "#" | "$" | "%" | "&" | "'" | + "(" | ")" | "*" | "+" | "," | "-" | "." | "/" | + "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | + "8" | "9" | ":" | ";" | "<" | "=" | ">" | "?" | + "@" | "A" | "B" | "C" | "D" | "E" | "F" | "G" | + "H" | "I" | "J" | "K" | "L" | "M" | "N" | "O" | + "P" | "Q" | "R" | "S" | "T" | "U" | "V" | "W" | + "X" | "Y" | "Z" | "[" | "]" | "^" | "_" | + "`" | "a" | "b" | "c" | "d" | "e" | "f" | "g" | + "h" | "i" | "j" | "k" | "l" | "m" | "n" | "o" | + "p" | "q" | "r" | "s" | "t" | "u" | "v" | "w" | + "x" | "y" | "z" | "{" | "|" | "}" | "~") : Literal | + "\\" . ( + ("\"" | "'" | "n" | "r" | "t" | "\\" | "0") : Ascii | + "x" . oct_digit . hex_digit : Oct | + "u{" .hex_digit + .opt(hex_digit + .opt(hex_digit + .opt(hex_digit + .opt(hex_digit . opt(hex_digit))))) . "}" : Unicode + ) : Escape ; let ws = plus(Pattern_Whitespace); - let punctuated(x, p) = [rec](x . opt(p . opt(ws) . rec)); - let list(x) = "(" . opt(ws) . [rec](x . opt("," . opt(ws) . opt(rec))) . ")"; + let punctuated(x, p) = [rec]((x : First) . (opt(p . opt(ws) . rec) : Next)); + let list(x) = "(" . opt(ws) . [rec]((x : First) . (opt("," . opt(ws) . opt(rec)) : Next)) . ")"; let epsilon = "_"; let ident = XID_Start . star(XID_Continue); - let literal = "\"" . plus(literal_char) . "\""; - let parens(expr) = "(" . opt(ws) . expr . ")"; - let fix(expr) = "[" . opt(ws) . ident . opt(ws) . "]" . opt(ws) . parens(expr); + let literal = "\"" . (plus(literal_char) : Contents) . "\""; + let parens(expr) = "(" . opt(ws) . (expr : Inner) . ")"; + let fix(expr) = "[" . opt(ws) . (ident : Arg) . opt(ws) . "]" . opt(ws) . (parens(expr) : Inner); let term(expr) = - epsilon . opt(ws) - | literal . opt(ws) - | parens(expr) . opt(ws) - | fix(expr) . opt(ws) - | ident . opt(ws) . opt(list(expr) . opt(ws)) + epsilon . opt(ws) : Epsilon + | literal . opt(ws) : Literal + | parens(expr) . opt(ws) : Parens + | fix(expr) . opt(ws) : Fix + | ident . opt(ws) . opt(list(expr) . opt(ws)) : CallOrVariable ; + let label = ":" . opt(ws) . (ident : Label) . opt(ws); let cat(expr) = punctuated(term(expr), "."); - let alt(expr) = punctuated(cat(expr), "|"); + let alt(expr) = punctuated((cat(expr) : Cat) . (opt(label) : Name), "|"); let expr = [expr](alt(expr)); - let let = "let" . ws . ident . opt(ws) . opt(list(ident . opt(ws)) . opt(ws)) . "=" . opt(ws) . expr . ";" . opt(ws); - let goal = "match" . ws . expr . ";" . opt(ws); + let let = "let" . ws . (ident : Name) . opt(ws) . (opt(list(ident . opt(ws)) . opt(ws)) : Args) . "=" . opt(ws) . (expr : Expr) . ";" . opt(ws); + let goal = "match" . ws . (expr : Expr) . ";" . opt(ws); - match star_(star_(goal, let), Pattern_Whitespace); + match star_(star_(goal : Goal, let : Let), Pattern_Whitespace); } -- cgit v1.2.3