LLAMA Syntax - Help Using the Parser

LLAMA Syntax Help:

Using the Parser

There are two variations of the Parser. The simple version looks only for the first possible parse of an input string. The full version finds all possible parses of an input string (i.e., it handles ambiguity).

The Simple Parser

The simple Parser looks something like the following (the exact look and feel of the Parser may vary from computer to computer):

At the top of the Parser is the Top Node Entry Field. Below that is the Parse Tree Window, and below that window are the Input String Entry Field and the Parse Button.

Entering a Top Node

A category must be entered in the Top Node Entry Field for the Parser to run. (It needs to know what type of structure to try to build.) To enter a Top Node, type any category in this field. As with all category entry fields, bar levels may be added and subtracted with the up and down arrow keys. The default Top Node is S.

Entering an Input String

To enter an input string, first click on the Input String Entry Field and then type. The input string can contain spaces.

Parsing an Input String

To parse an input string, simply click on the Parse Button. When the parse is completed, a tree will be drawn in the Parse Tree Window or a message will be displayed telling you that the input string could not be parsed.

Moving Around in the Parse Tree Window

Parse trees are sometimes larger than the Parse Tree Window. Under such circumstances you can move around in the Parse Tree Window using the scroll bars at the right and bottom of the window.

The scroll bars can be used in two ways:

You can click on the center portion of the bar and, holding down the mouse button, drag it around.
You can click on the arrows at the top and bottom (or right and left) of the scroll bar.

Some portion of the parse tree will be visible at all times.

The Full Parser

The Full Parser looks something like the following (the exact look and feel of the Parser may vary from computer to computer):

The only difference between the Full Parser and the Simple Parser is that the Full Parser has a Multiple Parses Checkbox, a Back Button, and a Forward Button next to the Top Node Entry Field.

Using the Multiple Parses Checkbox

If the checkbox is checked (or highlighted in some other way depending on the browser you are using), then the Parser will search for all possible parses of an input string. If it is not checked, it will search only for one successful parse. To change the setting of the checkbox, simply click on it once.

Using the Back and Forward Buttons

If the Parser has found more than one possible parse of an input string, the Forward Button will be active and you click on it to step through the parses. When you reach the last parse, the Forward Button will become inactive ("greyed out"). Similarly, you can go back to earlier parses with the Back Button and it will become inactive when you reach the first parse.