// Parse a postfix expr.
//
// postfix-expr ::= applicaiton-expr
Tree*
parse_postfix_expr(Parser& p) {
if (Tree* t1 = parse_primary_expr(p)) {
while (t1) {
if (Tree* t2 = parse_dot_expr(p, t1))
t1 = t2;
else if (Tree* t2 = parse_application_expr(p, t1))
t1 = t2;
else if (Tree* t2 = parse_and_expr(p, t1))
t1 = t2;
else if (Tree* t2 = parse_or_expr(p, t1))
t1 = t2;
else if (Tree* t2 = parse_eq_comp_expr(p, t1))
t1 = t2;
else if (Tree* t2 = parse_less_expr(p, t1))
t1 = t2;
else if (Tree* t2 = parse_union(p, t1))
t1 = t2;
else if (Tree* t2 = parse_intersect(p, t1))
t1 = t2;
else if (Tree* t2 = parse_except(p, t1))
t1 = t2;
else if (Tree* t2 = parse_join(p, t1))
t1 = t2;
else if (Tree* t2 = parse_as(p, t1))
t1 = t2;
else
break;
}
return t1;
}
return parse_primary_expr(p);
}
// Parse a mv expression.
// mv-expr ::= 'mv' string-expr string-expr
Tree*
parse_mv(Parser& p) {
if (const Token* k = parse::accept(p, mv_tok)) {
if (Tree* t = parse_primary_expr(p))
if (Tree* t1 = parse_primary_expr(p))
return new Mv_tree(k, t, t1);
else
parse::parse_error(p) << "expected 'string-expr' after 'mv'";
}
return nullptr;
}
// Parse a postfix expr.
//
// postfix-expr ::= applicaiton-expr
Tree*
parse_postfix_expr(Parser& p) {
if (Tree* t1 = parse_primary_expr(p)) {
while (t1) {
if (Tree* t2 = parse_dot_expr(p, t1))
t1 = t2;
else if (Tree* t2 = parse_application_expr(p, t1))
t1 = t2;
else
break;
}
return t1;
}
return parse_primary_expr(p);
}
// Parse a dot expression.
//
// dot-expr ::= postfix-expr '.' primary-expr
Tree*
parse_dot_expr(Parser& p, Tree* t1) {
if (parse::accept(p, dot_tok))
if (Tree* t2 = parse_primary_expr(p))
return new Dot_tree(t1, t2);
else
parse::parse_error(p) << "expected 'primary-expr' after '.'";
return nullptr;
}
// Parse a cd expression.
// cd-expr ::= 'cd' string-expr
Tree*
parse_cd(Parser& p) {
if (const Token* k = parse::accept(p, cd_tok)) {
if (Tree* t = parse_primary_expr(p))
return new Cd_tree(k, t);
else
parse::parse_error(p) << "expected 'string-expr' after 'cd'";
}
return nullptr;
}
// Parse a mkdir expression.
// mkdir-expr ::= 'mkdir' string-expr
Tree*
parse_mkdir(Parser& p) {
if (const Token* k = parse::accept(p, mkdir_tok)) {
/* if (parse::expect(p, equal_tok)){
parse::parse_error(p) << "expected 'string' after";
}
else{ */
if (Tree* t = parse_primary_expr(p))
return new Mkdir_tree(k, t);
else
parse::parse_error(p) << "expected 'string-expr' after 'mkdir'";
} //}
return nullptr;
}
// unary-expr ::= - unary expr
// + unary expr
// ! unary expr
// primary expr
Expr*
parse_unary_expr(Parser& p, Token_stream& ts)
{
if(ts.next()) {
switch (ts.next()->kind()) {
// negative
case minus_tok: return parse_neg(p, ts);
case plus_tok: return parse_pos(p, ts);
case bang_tok: return parse_not(p, ts);
default:
return parse_primary_expr(p, ts);
}
}
return nullptr;
}
static int
parse_unary_expr(int need_eval, cfg_cond_value_t *prv)
{
return parse_primary_expr(need_eval, prv);
}
// Parse an application expr.
//
// application-expr ::= postfix-expr primary-expr
Tree*
parse_application_expr(Parser& p, Tree* t1) {
if (Tree* t2 = parse_primary_expr(p))
return new App_tree(t1, t2);
return nullptr;
}
