expr symbol_::subs(const exmap &m) const
{
exmap::const_iterator it = m.find( this ), en = m.end();
if( it != en )
return it->second;
return this;
}
expr basic::subs_once(const exmap &map) const
{
auto end = map.cend();
auto it = map.find( this );
if( it != end )
return it->second.subs( map );
match_state s;
for( it = map.begin(); it != end; ++it )
if( match( it->first, s ) )
{
exmap m;
s.as_exmap( m );
return it->second.subs( m );
}
return this->eval(2);
}
/** Helper function for subs(). Does not recurse into subexpressions. */
ex basic::subs_one_level(const exmap & m, unsigned options) const
{
exmap::const_iterator it;
if (options & subs_options::no_pattern) {
ex thisex = *this;
it = m.find(thisex);
if (it != m.end())
return it->second;
return thisex;
} else {
for (it = m.begin(); it != m.end(); ++it) {
exmap repl_lst;
if (match(ex_to<basic>(it->first), repl_lst))
return it->second.subs(repl_lst, options | subs_options::no_pattern);
// avoid infinite recursion when re-substituting the wildcards
}
}
return *this;
}