ast_t* ast_from(ast_t* ast, token_id id)
{
assert(ast != NULL);
ast_t* new_ast = ast_token(token_dup_new_id(ast->t, id));
set_scope_no_parent(new_ast, ast->parent);
return new_ast;
}
static ast_t* duplicate(ast_t* parent, ast_t* ast)
{
if(ast == NULL)
return NULL;
assert(ast_id(ast) != TK_PROGRAM && ast_id(ast) != TK_PACKAGE &&
ast_id(ast) != TK_MODULE);
ast_t* n = ast_token(token_dup(ast->t));
n->data = ast->data;
n->flags = ast->flags & AST_ALL_FLAGS;
// We don't actually want to copy the orphan flag, but the following if
// always explicitly sets or clears it.
if(parent == NULL)
set_scope_no_parent(n, ast->parent);
else
set_scope_and_parent(n, parent);
n->child = duplicate(n, ast->child);
n->type = duplicate(n, ast->type);
if(ast->symtab != NULL)
n->symtab = symtab_dup(ast->symtab);
if(parent != NULL)
n->sibling = duplicate(parent, ast->sibling);
return n;
}
/* Load an ID node.
* IDs are indicated by the keyword id followed by the ID name, all contained
* within parentheses. For example:
* (id foo)
*
* The ( and id keyword must have been parsed before this is called.
*/
static ast_t* get_id(build_parser_t* builder, ast_t* existing_ast)
{
assert(builder != NULL);
if(existing_ast != NULL)
{
ast_free(existing_ast);
build_error(builder, "Seen ID not first in node");
return NULL;
}
ast_token_id id = get_token(builder);
if(id != AT_ID && id != AT_STRING)
{
build_error(builder, "ID name expected");
return NULL;
}
ast_t* ast = ast_token(builder->token);
ast_setid(ast, TK_ID);
save_token(builder);
if(get_token(builder) != AT_RPAREN)
{
build_error(builder, "Close paren expected for ID");
ast_free(ast);
return NULL;
}
return ast;
}
static ast_t* consume_token(parser_t* parser)
{
ast_t* ast = ast_token(parser->token);
ast_setflag(ast, parser->next_flags);
parser->next_flags = 0;
fetch_next_lexer_token(parser, false);
return ast;
}
ast_t* ast_from_float(ast_t* ast, double value)
{
assert(ast != NULL);
token_t* t = token_dup(ast->t);
token_set_id(t, TK_FLOAT);
token_set_float(t, value);
ast_t* new_ast = ast_token(t);
set_scope_no_parent(new_ast, ast->parent);
return new_ast;
}
ast_t* ast_from_int(ast_t* ast, uint64_t value)
{
assert(ast != NULL);
token_t* t = token_dup(ast->t);
token_set_id(t, TK_INT);
lexint_t lexint = {value, 0};
token_set_int(t, &lexint);
ast_t* new_ast = ast_token(t);
set_scope_no_parent(new_ast, ast->parent);
return new_ast;
}
ast_t* ast_from_string(ast_t* ast, const char* name)
{
if(name == NULL)
return ast_from(ast, TK_NONE);
token_t* t = token_dup(ast->t);
token_set_id(t, TK_ID);
token_set_string(t, name, 0);
ast_t* new_ast = ast_token(t);
set_scope_no_parent(new_ast, ast->parent);
return new_ast;
}
// Process any deferred token we have
static void process_deferred_ast(parser_t* parser, rule_state_t* state)
{
assert(parser != NULL);
assert(state != NULL);
if(state->deferred)
{
token_t* deferred_token = token_new(state->deferred_id);
token_set_pos(deferred_token, parser->source, state->line, state->pos);
state->ast = ast_token(deferred_token);
state->deferred = false;
}
}
ast_t* ast_blank(token_id id)
{
return ast_token(token_new(id));
}
ast_t* ast_new(token_t* t, token_id id)
{
return ast_token(token_dup_new_id(t, id));
}
// Load a sequence of nodes until the specified terminator is found
static ast_t* get_nodes(build_parser_t* builder, ast_token_id terminator)
{
assert(builder != NULL);
ast_t* ast = NULL;
ast_t* last_child = NULL;
while(true)
{
ast_token_id id = get_token(builder);
ast_t* child = NULL;
bool is_type = false;
if(id == terminator)
{
if(ast == NULL)
build_error(builder, "Syntax error");
if(ast_id(ast) == TK_MINUS && ast_childcount(ast) == 1)
ast_setid(ast, TK_UNARY_MINUS);
return ast;
}
if(id == AT_ID)
id = keyword_replace(builder);
switch(id)
{
case AT_LPAREN:
child = get_nodes(builder, AT_RPAREN);
break;
case AT_LSQUARE:
child = get_type(builder, ast);
is_type = true;
break;
case AT_ERROR: // Propogate
break;
case AT_STRING:
case AT_TOKEN:
child = ast_token(builder->token);
save_token(builder);
get_attributes(builder, child);
break;
case AT_ID:
if(strcmp("id", token_string(builder->token)) == 0)
return get_id(builder, ast);
build_error(builder, "Unrecognised identifier \"%s\"",
token_string(builder->token));
break;
default:
build_error(builder, "Syntax error");
break;
}
if(child == NULL)
{
// An error occurred and should already have been reported
ast_free(ast);
return NULL;
}
if(ast == NULL)
{
ast = child;
last_child = NULL;
}
else if(is_type)
{
ast_settype(ast, child);
}
else
{
if(last_child == NULL)
ast_add(ast, child);
else
ast_add_sibling(last_child, child);
last_child = child;
}
}
}
