diff options
| -rw-r--r-- | grammars/bpeg.bp | 39 |
1 files changed, 19 insertions, 20 deletions
diff --git a/grammars/bpeg.bp b/grammars/bpeg.bp index 4855255..e8d7259 100644 --- a/grammars/bpeg.bp +++ b/grammars/bpeg.bp @@ -1,23 +1,22 @@ # This is a file defining the BP grammar using BP syntax -Grammar: __ *(Def [__`;])%__ __ ($$ / @!=(..%\n => "Could not parse this code")) -Def: @name=id _ `: __ ( +Grammar: __ *(Def [__`;])%__ __ ($$ / @!=(..$$%\n => "Could not parse this code")) +Def: @name=id __ `: __ ( @definition=extended-pat / $$ @!=(''=>"No definition for rule") / @!=(..>(`;/id_`:/$)%\n => "Invalid definition: @0")) # This is used for command line arguments: -String-pattern: .. % (\n / Nodent / Escape / `\ pat [`;]) +String-pattern: ..$$ % (\n / Nodent / Escape / `\ pat [`;]) -pat: simple-pat !(__("!="/"=="/"=>")) / suffixed-pat +pat: simple-pat !(__("!="/"==")) / suffixed-pat simple-pat: Upto-and / Dot / String / Chars / Nodent / Escape-range - / Escape / Repeat / Optional / After / Before / Capture + / Escape / Repeat / Optional / No / After / Before / Capture / Ref / parens suffixed-pat: ( Eq-pat / Not-eq-pat - / Replace ) Eq-pat: @first=pat__"=="__@second=pat @@ -28,7 +27,7 @@ String: ( `" @s=*(Escape / !`".) (`" / @!=(''=> "Expected closing quote here")) / `' @s=*(Escape / !`'.) (`' / @!=(''=> "Expected closing quote here")) ) -Chars: `` @+(Char/Char-range) % `, +Chars: `` @+(Char-range/Char) % `, Char-range: @low=. `- (@high=. / @!=(''=> "Expected a second character to form a character range")) Char: (@s=. / @!=(''=> "Expected a character following the '`'")) Escape-range: `\ @low=escape-sequence `- @high=escape-sequence @@ -41,29 +40,29 @@ escape-sequence: ( / 1-3 `0-7 / `x 2 `0-9,a-f,A-F ) -No: `! (_@pat / @!=(''=>"Expected a pattern after the exclamation mark")) +No: `! (__@pat / @!=(''=>"Expected a pattern after the exclamation mark")) Nodent: `\ `N -Upto-and: 2-3`. [_@first=simple-pat] [__`%__@second=simple-pat] +Upto-and: ".." [__@first=simple-pat] [__`%__@second=simple-pat] Repeat: ( - @min='' `* @max='' - / @min=int _ `- _ @max=int - / @min=int _ `+ @max='' + @min=(''=>'0') `* @max='' + / @min=int __ `- __ @max=int + / @min=(int / ''=>'1') __ `+ @max='' / @min=@max=int ) __ @repeat-pat=pat [__`%__@sep=pat] Optional: `[ __ extended-pat (__`] / @!=(''=> "Expected closing square bracket here")) -After: `< _ pat -Before: `> _ pat -Capture: `@ [_ @capture-name=(id/`!) __ !"=>" `=] __ (@capture=pat / @!=(''=> "Expected pattern to capture")) +After: `< __ pat +Before: `> __ pat +Capture: `@ [__ @capture-name=(id/`!) __ !"=>" `=] __ (@capture=pat / @!=(''=> "Expected pattern to capture")) Replace: ( - @replace-pat=pat __ "=>" (__ @replacement=String / @!=(''=> "Expected replacement string")) + @replace-pat=(Replace / Chain / pat) __ "=>" (__ @replacement=String / @!=(''=> "Expected replacement string")) ) -Ref: @name=id !(_`:) +Ref: @name=id !(__`:) parens: `( __ extended-pat (__ `) / @!=(''=> "Expected closing parenthesis here")) -Chain: 2+@pat%__ -Otherwise: 2+@(Chain/pat)%(__`/__) -extended-pat: Otherwise / Chain / pat +Chain: 2+@(pat !(__"=>") / Replace)%__ +Otherwise: 2+@(Replace / Chain / pat)%(__`/__) +extended-pat: Otherwise / Replace / Chain / pat # Special-symbol rules: _: *(` / \t) |