Instead of entering some text to be anagrammed, you can enter a pattern to find matching words in the current lexicon. As you type in a pattern the "Find Usable Words" button automatically changes to "Find Matching Words". Here are some example patterns:

* Find all words in the lexicon.
*x* Find words that contain the letter "x".
!*x* Find words that don't contain "x".
~*x* Ditto (~ is equivalent to !).
*ed Find words ending with "ed".
*(ed|ing) Find words ending with "ed" or "ing".
??? Find words with 3 letters.
?10 Find words with 10 letters.
?7-10 Find words with 7 to 10 letters.
?7- Find words with at least 7 letters.
?-7 Find words with at most 7 letters.
*x*&*y* Find words containing "x" and "y" in any order.
[xyz]* Find words starting with "x", "y" or "z".
[!aeiou]- Find words with no vowels.

Let's look at some more complicated patterns. Note that spaces are ignored and can be used to make a long pattern more readable. This example will find all words containing a single "a":

[!a]- a [!a]-

This example finds all words containing "i" and "n" and "g" (in any order) but not ending in "ing":

*i* & *n* & *g* & (!*ing)

NOTE: When using patterns with a numeric lexicon you need to enclose a repeat count in angle brackets to avoid any ambiguity. For example, if you want to find all 3-digit numbers then use the pattern "?<3>" rather than "?3" (the latter will find all 2-digit numbers ending with 3). Angle brackets can also be used in patterns for a non-numeric lexicon.

The above examples illustrate all of the special pattern characters:

* Match zero or more letters.
? Match any single letter.
[...] Match any letter in the given list; eg. [abc].
[!...] Match any letter NOT in the given list; eg. [!aeiou].
N Specifies a fixed repeat count, where N is a non-negative integer. Repeat counts are only allowed after ?, ], or a letter; eg. ?9.
M-N Specifies a variable repeat count. M and N are optional non-negative integers indicating the minimum and maximum counts. If M is missing then 0 is assumed, and if N is missing then infinity is assumed. Note that * is equivalent to ?-.
<...> Any repeat count can be enclosed in angle brackets; eg. <2-5>. This form of a repeat count is necessary when using a numeric lexicon (where digits are valid "letters").
- Used inside [...] to indicate a letter range; eg. [a-z], or to separate min and max repeat counts; eg. 2-5.
(...) Match a sub-pattern; eg. (a|b)*.
| Means OR. For matching alternative patterns; eg. a*|b*.
& Means AND. For matching combined patterns; eg. *a*&*b*.
! Means NOT. Can only be the first character in the pattern or the first character after ( or [.
~ Also means NOT. Useful when entering patterns on the agc command line.

Patterns can also be typed into the Edit menu's "Find Word(s)" dialog to find and select matching words in the current list of usable/lexicon words.