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Fixed keyword boundary problem.

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yhirose 2015-08-05 23:06:07 -04:00
parent 6b690dd3cb
commit ef476b87cf
1 changed files with 12 additions and 11 deletions
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23
language/pl0/pl0.cc
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@ -20,21 +20,21 @@ auto grammar = R"(
program <- _ block '.' _
block <- const var procedure statement
const <- ('CONST' _ ident '=' _ number (',' _ ident '=' _ number)* ';' _)?
var <- ('VAR' _ ident (',' _ ident)* ';' _)?
procedure <- ('PROCEDURE' _ ident ';' _ block ';' _)*
const <- ('CONST' __ ident '=' _ number (',' _ ident '=' _ number)* ';' _)?
var <- ('VAR' __ ident (',' _ ident)* ';' _)?
procedure <- ('PROCEDURE' __ ident ';' _ block ';' _)*
statement <- (assignment / call / statements / if / while / out / in)?
assignment <- ident ':=' _ expression
call <- 'CALL' _ ident
statements <- 'BEGIN' _ statement (';' _ statement )* 'END' _
if <- 'IF' _ condition 'THEN' _ statement
while <- 'WHILE' _ condition 'DO' _ statement
out <- ('out' / 'write' / '!') _ expression
in <- ('in' / 'read' / '?') _ ident
call <- 'CALL' __ ident
statements <- 'BEGIN' __ statement (';' _ statement )* 'END' __
if <- 'IF' __ condition 'THEN' __ statement
while <- 'WHILE' __ condition 'DO' __ statement
out <- ('out' __ / 'write' __ / '!' _) expression
in <- ('in' __ / 'read' __ / '?' _) ident
condition <- odd / compare
odd <- 'ODD' _ expression
odd <- 'ODD' __ expression
compare <- expression compare_op expression
compare_op <- < '=' / '#' / '<=' / '<' / '>=' / '>' > _
@ -47,10 +47,11 @@ auto grammar = R"(
factor <- ident / number / '(' _ expression ')' _
ident <- < [a-z] ([a-z] / [0-9])* > _
ident <- < [a-z] [a-z0-9]* > _
number <- < [0-9]+ > _
~_ <- [ \t\r\n]*
~__ <- ![a-z0-9_] _
)";
/*