diff options
Diffstat (limited to 'filter')
| -rw-r--r-- | filter/filter.c | 32 |
1 files changed, 15 insertions, 17 deletions
diff --git a/filter/filter.c b/filter/filter.c index 107c4229..a7a17bd4 100644 --- a/filter/filter.c +++ b/filter/filter.c @@ -10,25 +10,23 @@ /** * DOC: Filters * - * You can find sources of filters language in |filter/| - * directory. |filter/config.Y| filter grammar, and basically translates - * source from user into tree of &f_inst structures. These trees are - * later interpreted using code in |filter/filter.c|. Filters internally - * work with values/variables in struct f_val, which contains type of - * value and value. + * You can find sources of the filter language in |filter/| + * directory. File |filter/config.Y| contains filter grammar and basically translates + * the source from user into a tree of &f_inst structures. These trees are + * later interpreted using code in |filter/filter.c|. * - * Filter consists of tree of &f_inst structures, one structure per - * "instruction". Each &f_inst contains code, aux value which is - * usually type of data this instruction operates on, and two generic - * arguments (a1, a2). Some instructions contain pointer(s) to other - * instructions in their (a1, a2) fields. + * A filter is represented by a tree of &f_inst structures, one structure per + * "instruction". Each &f_inst contains @code, @aux value which is + * usually the data type this instruction operates on and two generic + * arguments (@a1, @a2). Some instructions contain pointer(s) to other + * instructions in their (@a1, @a2) fields. * - * Filters use structure &f_val for its variables. Each &f_val - * contains type and value. Types are constants prefixed with %T_. Few - * of types are special; %T_RETURN can be or-ed with type to indicate - * that return from function/from whole filter should be - * forced. Important thing about &f_val s is that they may be copied - * with simple =. That's fine for all currently defined types: strings + * Filters use a &f_val structure for their data. Each &f_val + * contains type and value (types are constants prefixed with %T_). Few + * of the types are special; %T_RETURN can be or-ed with a type to indicate + * that return from a function or from the whole filter should be + * forced. Important thing about &f_val's is that they may be copied + * with a simple |=|. That's fine for all currently defined types: strings * are read-only (and therefore okay), paths are copied for each * operation (okay too). */ |