find-max and find-min support hashes.

* lib.c (find_max): Restructured to implement separately
for vectors and lists. Support hash tables.

* txr.1: Document find-min and find-max for hashes.

1 files changed, 21 insertions, 2 deletions

diff --git a/txr.1 b/txr.1
index f19603cc..8569f797 100644
--- a/txr.1
+++ b/txr.1
@@ -23877,8 +23877,8 @@ the leftmost.
 
 .coNP Functions @ find-max and @ find-min
 .synb
-.mets (find-max < sequence >> [ testfun <> [ keyfun ]])
-.mets (find-min < sequence >> [ testfun <> [ keyfun ]])
+.mets (find-max >> { sequence | << hash } >> [ testfun <> [ keyfun ]])
+.mets (find-min >> { sequence | << hash } >> [ testfun <> [ keyfun ]])
 .syne
 .desc
 The
@@ -23940,6 +23940,25 @@ is passed through this one-argument function, and
 the resulting value is used in its place for the purposes of the
 comparison. However, the original element is returned.
 
+A hash table may be specified instead of a sequence.
+The
+.meta hash
+is treated as if it were a sequence of hash key and hash
+value pairs represented as cons cells, the
+.code car
+slots of which are the hash keys, and the
+.code cdr
+of which are the hash values.  If the caller doesn't specify a
+.meta keyfun
+then these cells are taken as their keys. To find the hash
+table's key-value cell with the maximum key, the
+.code car
+function can be specified as
+.metn keyfun .
+To find the entry holding the maximum value, the
+.code cdr
+function can be specified.
+
 .coNP Function @ set-diff
 .synb
 .mets (set-diff < seq1 < seq2 >> [ testfun <> [ keyfun ]])