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docs/comparison.md

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+# Comparison
+
+Compare values and produce boolean results (0 or 1).
+
+## Equality
+
+```forth
+3 3 =    ( 1 - equal )
+3 4 =    ( 0 - not equal )
+3 4 !=   ( 1 - not equal )
+3 4 <>   ( 1 - not equal, alternative )
+```
+
+## Ordering
+
+```forth
+2 3 lt   ( 1 - less than )
+3 2 gt   ( 1 - greater than )
+3 3 <=   ( 1 - less or equal )
+3 3 >=   ( 1 - greater or equal )
+```
+
+## With Conditionals
+
+```forth
+step 4 lt { "kick" s . } ?  ( kick on first 4 steps )
+
+beat 8 >= { 0.5 gain } ?    ( quieter after beat 8 )
+```
+
+## Words
+
+| Word | Stack | Description |
+|------|-------|-------------|
+| `=` | (a b -- bool) | Equal |
+| `!=` | (a b -- bool) | Not equal |
+| `<>` | (a b -- bool) | Not equal (alias) |
+| `lt` | (a b -- bool) | Less than |
+| `gt` | (a b -- bool) | Greater than |
+| `<=` | (a b -- bool) | Less or equal |
+| `>=` | (a b -- bool) | Greater or equal |