From 19d4e4da6a93deb398f87bb6b42b1b1ee3c4926e Mon Sep 17 00:00:00 2001
From: Marshall Lochbaum <mwlochbaum@gmail.com>
Date: Mon, 15 Feb 2021 20:52:54 -0500
Subject: =?UTF-8?q?Give=20an=20empty=20result,=20not=20an=20error,=20whene?=
 =?UTF-8?q?ver=20=F0=9D=95=A8=20is=20longer=20than=20=F0=9D=95=A9=20in=20F?=
 =?UTF-8?q?ind?=
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---
 spec/primitive.md  | 2 +-
 spec/reference.bqn | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

(limited to 'spec')

diff --git a/spec/primitive.md b/spec/primitive.md
index 95fd9392..386b0dcf 100644
--- a/spec/primitive.md
+++ b/spec/primitive.md
@@ -197,7 +197,7 @@ Dyadic search functions check whether major cells of the *principal argument* (w
 - **Index of** (`⊐`) gives the smallest index of a principal argument cell that matches the cell, or `≠𝕨` if there is no such cell.
 - **Progressive Index of** (`⊒`) processes non-principal cells in ravel order, and gives the smallest index of a principal argument cell that matches the cell that hasn't already been included in the result. Again `≠𝕨` is returned for a given cell if there is no valid cell.
 
-**Find** (`⍷`) indicates positions where `𝕨` appears as a contiguous subarray of a `=𝕨`-cell of `𝕩`. It has one result element for each such subarray of `𝕩`, whose value is 1 if that subarray matches `𝕩` and 0 otherwise.
+**Find** (`⍷`) indicates positions where `𝕨` appears as a contiguous subarray of a `=𝕨`-cell of `𝕩`. It has one result element for each such subarray of `𝕩`, whose value is 1 if that subarray matches `𝕩` and 0 otherwise. Find cannot result in an error unless the rank of `𝕨` is higher than that of `𝕩`. If `𝕨` is longer along one axis than the corresponding trailing axis of `𝕩`, then the result has length 0 along that axis. Any atom argument to Find is automatically enclosed.
 
 ### Sorting
 
diff --git a/spec/reference.bqn b/spec/reference.bqn
index c3719144..adad4f13 100644
--- a/spec/reference.bqn
+++ b/spec/reference.bqn
@@ -414,8 +414,8 @@ MarkFirst←{
 Find←{
   r←=𝕨
   ! r≤=𝕩
-  𝕨 ≡⎉r (≢𝕨) ↕⎉r 𝕩
-}
+  𝕨 ≡⎉r ((1+r-⊸↑≢𝕩)⌊≢𝕨)⊸↕⎉r 𝕩
+}○ToArray
 
 ReorderAxes←{
   𝕩↩<⍟(0=≡)𝕩
-- 
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