Implementation of new parser
From Aikiframework wiki
Concept
Parser for AIKI markup should be real recursive parser (no lame string substitution) it should parse things like this:
(for( $aiki->utils->fn() as id {
<div>
(sql( SELECT * FROM table WHERE id = ((id)) {
<div>
<h1>Section 1</h1>
(if( $aiki->utls->fn( ((some_filed)) ) {
<div>((some_filed))</div>
(*here id will be from first sql not from for loop*)
(sql( SELECT * FROM other_table WHERE ((other_id)) = ((id)) {
(if( $aiki->membership->username == '[username]' ||
$aiki->membership->permission == 'librarian'{
(*here id will be from last sql not from for loop nor first sql *)
(widget:delete_row( "other_table", ((id)) )widget)
})if)
})sql)
})if)
</h2>Section 2</h2>
(if( $aiki->utls->file_exists( ((filename)) ) {
(widget:show_file( ((filename)) )widget)
}else{
<div>Sorry no file</div>
})if)
</div>
})sql)
</div>
})for)
No matter how deeply nested the markup will be it should handle it.
We should use parser generator for this job - PEG is nice grammar.
And after parsing it should evaluate the markup and return widget content.
