// limbo.rl
// http://www.vitanuova.com/inferno/papers/limbo.html
/************************* Required for every parser *************************/
#ifndef RAGEL_LIMBO_PARSER
#define RAGEL_LIMBO_PARSER
#include "../parser_macros.h"
// the name of the language
const char *LIMBO_LANG = "limbo";
// the languages entities
const char *limbo_entities[] = {
"space", "comment", "string", "number",
"keyword", "identifier", "operator", "any"
};
// constants associated with the entities
enum {
LIMBO_SPACE = 0, LIMBO_COMMENT, LIMBO_STRING, LIMBO_NUMBER,
LIMBO_KEYWORD, LIMBO_IDENTIFIER, LIMBO_OPERATOR, LIMBO_ANY
};
/*****************************************************************************/
%%{
machine limbo;
write data;
include common "common.rl";
# Line counting machine
action limbo_ccallback {
switch(entity) {
case LIMBO_SPACE:
ls
break;
case LIMBO_ANY:
code
break;
case INTERNAL_NL:
std_internal_newline(LIMBO_LANG)
break;
case NEWLINE:
std_newline(LIMBO_LANG)
}
}
limbo_comment = '#' @comment nonnewline*;
limbo_sq_str =
'\'' @code (
[^\r\n\f\t '\\] @code
|
'\\' nonnewline @code
)* '\'' @commit;
limbo_dq_str =
'"' @enqueue @code (
[^\r\n\f\t "\\] @code
|
'\\' nonnewline @code
)* '"' @commit;
limbo_string = limbo_sq_str | limbo_dq_str;
limbo_line := |*
spaces ${ entity = LIMBO_SPACE; } => limbo_ccallback;
limbo_comment;
limbo_string;
newline ${ entity = NEWLINE; } => limbo_ccallback;
^space ${ entity = LIMBO_ANY; } => limbo_ccallback;
*|;
# Entity machine
action limbo_ecallback {
callback(LIMBO_LANG, limbo_entities[entity], cint(ts), cint(te), userdata);
}
limbo_comment_entity = '#' nonnewline*;
# todo: this probably allows multi-line strings too, which limbo doesn't allow?
limbo_string_entity = sq_str_with_escapes | dq_str_with_escapes;
# todo: support numbers with specified radix? e.g. 16rFF, 8r666, 2b10101
limbo_number_entity = float | integer;
# todo: support utf-8 identifiers
limbo_identifier_entity = (alpha | '_') (alnum | '_')*;
limbo_keyword_entity =
'alt' | 'break' | 'continue' | 'exit' | 'return' | 'spawn' | 'implement' | 'import' | 'load' | 'raise' | 'raises'
'include' | 'array' | 'big' | 'byte' | 'chan' | 'con' | 'int' | 'list' | 'real' | 'string' | 'fn' |
'adt' | 'pick' | 'module' |
'for' | 'while' | 'do' |
'if' | 'else' | 'case' | 'or' | 'to' |
'=>' |
'ref' | 'self' | 'cyclic' | 'type' | 'of' |
'tl' | 'hd' | 'len' | 'tagof' |
'nil';
limbo_operator_entity = [+\-/*%!=^&|~:;.,()\[\]{}>];
limbo_entity := |*
space+ ${ entity = LIMBO_SPACE; } => limbo_ecallback;
limbo_comment_entity ${ entity = LIMBO_COMMENT; } => limbo_ecallback;
limbo_string_entity ${ entity = LIMBO_STRING; } => limbo_ecallback;
limbo_number_entity ${ entity = LIMBO_NUMBER; } => limbo_ecallback;
limbo_keyword_entity ${ entity = LIMBO_KEYWORD; } => limbo_ecallback;
limbo_identifier_entity ${ entity = LIMBO_IDENTIFIER; } => limbo_ecallback;
limbo_operator_entity ${ entity = LIMBO_OPERATOR; } => limbo_ecallback;
^(space | digit) ${ entity = C_ANY; } => limbo_ecallback;
*|;
}%%
/************************* Required for every parser *************************/
/* Parses a string buffer with Limbo code.
*
* @param *buffer The string to parse.
* @param length The length of the string to parse.
* @param count Integer flag specifying whether or not to count lines. If yes,
* uses the Ragel machine optimized for counting. Otherwise uses the Ragel
* machine optimized for returning entity positions.
* @param *callback Callback function. If count is set, callback is called for
* every line of code, comment, or blank with 'lcode', 'lcomment', and
* 'lblank' respectively. Otherwise callback is called for each entity found.
*/
void parse_limbo(char *buffer, int length, int count,
void (*callback) (const char *lang, const char *entity, int s,
int e, void *udata),
void *userdata
) {
init
%% write init;
cs = (count) ? limbo_en_limbo_line : limbo_en_limbo_entity;
%% write exec;
// if no newline at EOF; callback contents of last line
if (count) { process_last_line(LIMBO_LANG) }
}
#endif
/*****************************************************************************/