diff options
Diffstat (limited to 'src/expr.h')
| -rw-r--r-- | src/expr.h | 28 |
1 files changed, 20 insertions, 8 deletions
@@ -86,8 +86,10 @@ struct bfs_exprs { * A command line expression. */ struct bfs_expr { - /** The next allocated expression. */ + /** This expression's next sibling, if any. */ struct bfs_expr *next; + /** The next allocated expression. */ + struct { struct bfs_expr *next; } freelist; /** The function that evaluates this expression. */ bfs_eval_fn *eval_fn; @@ -123,12 +125,7 @@ struct bfs_expr { /** Auxilliary data for the evaluation function. */ union { /** Child expressions. */ - struct { - /** The left hand side of the expression. */ - struct bfs_expr *lhs; - /** The right hand side of the expression. */ - struct bfs_expr *rhs; - }; + struct bfs_exprs children; /** Integer comparisons. */ struct { @@ -218,11 +215,26 @@ struct bfs_ctx; struct bfs_expr *bfs_expr_new(struct bfs_ctx *ctx, bfs_eval_fn *eval, size_t argc, char **argv); /** - * @return Whether the expression has child expressions. + * @return Whether this type of expression has children. */ bool bfs_expr_is_parent(const struct bfs_expr *expr); /** + * @return The first child of this expression, or NULL if it has none. + */ +struct bfs_expr *bfs_expr_children(const struct bfs_expr *expr); + +/** + * Add a child to an expression. + */ +void bfs_expr_append(struct bfs_expr *expr, struct bfs_expr *child); + +/** + * Add a list of children to an expression. + */ +void bfs_expr_extend(struct bfs_expr *expr, struct bfs_exprs *children); + +/** * @return Whether expr is known to always quit. */ bool bfs_expr_never_returns(const struct bfs_expr *expr); |