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docs/generators.md

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+# Generators
+
+Create sequences of values on the stack.
+
+## Arithmetic Range
+
+The `..` operator pushes an arithmetic sequence:
+
+```forth
+1 4 ..     ( pushes 1 2 3 4 )
+60 67 ..   ( pushes 60 61 62 63 64 65 66 67 )
+```
+
+## Geometric Range
+
+The `geom..` operator creates a geometric sequence:
+
+```forth
+1 2 4 geom..   ( pushes 1 2 4 8 )
+100 0.5 4 geom..  ( pushes 100 50 25 12.5 )
+```
+
+Stack: `(start ratio count -- values...)`
+
+## Generate
+
+The `gen` word executes a quotation multiple times:
+
+```forth
+{ 1 6 rand } 4 gen  ( 4 random values from 1-6 )
+{ coin } 8 gen      ( 8 random 0/1 values )
+```
+
+## Examples
+
+Random melody:
+
+```forth
+"pluck" s
+  { 48 72 rand } 4 gen 4 choose note
+.
+```
+
+Chord from range:
+
+```forth
+"pad" s
+  60 67 .. 8 choose note  ( random note in octave )
+.
+```
+
+Euclidean-style rhythm values:
+
+```forth
+0 1 0 0 1 0 1 0  ( manual )
+{ coin } 8 gen   ( random 8-step pattern )
+```
+
+## Words
+
+| Word | Stack | Description |
+|------|-------|-------------|
+| `..` | (start end -- values...) | Arithmetic sequence |
+| `geom..` | (start ratio count -- values...) | Geometric sequence |
+| `gen` | (quot n -- results...) | Execute quotation n times |