diff --git a/c/mapping/mapper_put_or_filter.c b/c/mapping/mapper_put_or_filter.c
index 100608f54..2122e21bb 100644
--- a/c/mapping/mapper_put_or_filter.c
+++ b/c/mapping/mapper_put_or_filter.c
@@ -221,6 +221,7 @@ static void shared_usage(FILE* o, char* argv0, char* verb) {
 	fprintf(o, "    %s %s put 'begin {@foo = 97} $column += @foo'.\n", argv0, verb);
 	fprintf(o, "    The value part is subject to type-inferencing as specified by -S/-F.\n");
 	fprintf(o, "    May be specified more than once, e.g. -s name1=value1 -s name2=value2.\n");
+	fprintf(o, "    Note: the value may be an environment variable, e.g. -s sequence=$SEQUENCE\n");
 	fprintf(o, "\n");
 
 	fprintf(o, "Tracing options:\n");
diff --git a/doc/content-for-reference-verbs.html b/doc/content-for-reference-verbs.html
index f1d875a86..574990324 100644
--- a/doc/content-for-reference-verbs.html
+++ b/doc/content-for-reference-verbs.html
@@ -194,6 +194,20 @@ POKI_RUN_COMMAND{{mlr --icsv --ojson clean-whitespace data/clean-whitespace.csv}
 <li/> <a href="./reference-verbs.html/#clean_whitespace">clean_whitespace</a>
 </ul>
 
+</div>
+<!-- ================================================================ -->
+<h1>count</h1>
+<button style="font-weight:bold;color:maroon;border:0" padding=0 onclick="bodyToggler.toggle('body_section_toggle_count');" href="javascript:;">Toggle section visibility</button>
+<div id="body_section_toggle_count" style="display: block">
+
+POKI_RUN_COMMAND{{mlr count --help}}HERE
+
+POKI_RUN_COMMAND{{mlr count data/medium}}HERE
+
+POKI_RUN_COMMAND{{mlr count -g a data/medium}}HERE
+
+POKI_RUN_COMMAND{{mlr count -g a,b data/medium}}HERE
+
 </div>
 <!-- ================================================================ -->
 <h1>count-distinct</h1>
diff --git a/doc/cookbook.html b/doc/cookbook.html
index 150202aa3..2a4d1938c 100644
--- a/doc/cookbook.html
+++ b/doc/cookbook.html
@@ -858,7 +858,7 @@ date,qoh
 <div class="pokipanel">
 <pre>
 $ wc -l data/miss-date.csv
-1372 data/miss-date.csv
+    1372 data/miss-date.csv
 </pre>
 </div>
 <p/>
diff --git a/doc/data-examples.html b/doc/data-examples.html
index c8bcf0b6d..6f4c434e3 100644
--- a/doc/data-examples.html
+++ b/doc/data-examples.html
@@ -208,7 +208,7 @@ St. Johns  -                      -                       -
 <div class="pokipanel">
 <pre>
 $ wc -l data/colored-shapes.dkvp
-10078 data/colored-shapes.dkvp
+   10078 data/colored-shapes.dkvp
 </pre>
 </div>
 <p/>
diff --git a/doc/data-sharing.html b/doc/data-sharing.html
index f6b274e37..6c8f3801f 100644
--- a/doc/data-sharing.html
+++ b/doc/data-sharing.html
@@ -417,11 +417,11 @@ wye pan 5 0.5732889198020006  0.8636244699032729  {5}
 <pre>
 $ mlr --opprint put '$o = system("echo -n ".$a."| sha1sum")' data/small
 a   b   i x                   y                   o
-pan pan 1 0.3467901443380824  0.7268028627434533  bd2bd8216b9cb4aa5a12daa6cfc98eef2ee20e56  -
-eks pan 2 0.7586799647899636  0.5221511083334797  16191338e81a46c7d127f5c8899f5c92e3cd38e3  -
-wye wye 3 0.20460330576630303 0.33831852551664776 14ba3c3e96a2474ab6dc7409ebf9d6b9cc3d84f0  -
-eks wye 4 0.38139939387114097 0.13418874328430463 16191338e81a46c7d127f5c8899f5c92e3cd38e3  -
-wye pan 5 0.5732889198020006  0.8636244699032729  14ba3c3e96a2474ab6dc7409ebf9d6b9cc3d84f0  -
+pan pan 1 0.3467901443380824  0.7268028627434533  f29c748220331c273ef16d5115f6ecd799947f13  -
+eks pan 2 0.7586799647899636  0.5221511083334797  456d988ecb3bf1b75f057fc6e9fe70db464e9388  -
+wye wye 3 0.20460330576630303 0.33831852551664776 eab0de043d67f441c7fd1e335f0ca38708e6ebf7  -
+eks wye 4 0.38139939387114097 0.13418874328430463 456d988ecb3bf1b75f057fc6e9fe70db464e9388  -
+wye pan 5 0.5732889198020006  0.8636244699032729  eab0de043d67f441c7fd1e335f0ca38708e6ebf7  -
 </pre>
 </div>
 <p/>
diff --git a/doc/manpage.html b/doc/manpage.html
index 39bfa47ad..c2cd16faa 100644
--- a/doc/manpage.html
+++ b/doc/manpage.html
@@ -636,6 +636,7 @@ VERBS
 	   mlr filter put 'begin {@foo = 97} $column += @foo'.
 	   The value part is subject to type-inferencing as specified by -S/-F.
 	   May be specified more than once, e.g. -s name1=value1 -s name2=value2.
+	   Note: the value may be an environment variable, e.g. -s sequence=$SEQUENCE
 
        Tracing options:
        -v: Prints the expressions's AST (abstract syntax tree), which gives
@@ -1009,6 +1010,7 @@ VERBS
 	   mlr put put 'begin {@foo = 97} $column += @foo'.
 	   The value part is subject to type-inferencing as specified by -S/-F.
 	   May be specified more than once, e.g. -s name1=value1 -s name2=value2.
+	   Note: the value may be an environment variable, e.g. -s sequence=$SEQUENCE
 
        Tracing options:
        -v: Prints the expressions's AST (abstract syntax tree), which gives
diff --git a/doc/manpage.txt b/doc/manpage.txt
index b17420cf3..924401de6 100644
--- a/doc/manpage.txt
+++ b/doc/manpage.txt
@@ -562,6 +562,7 @@ VERBS
 	   mlr filter put 'begin {@foo = 97} $column += @foo'.
 	   The value part is subject to type-inferencing as specified by -S/-F.
 	   May be specified more than once, e.g. -s name1=value1 -s name2=value2.
+	   Note: the value may be an environment variable, e.g. -s sequence=$SEQUENCE
 
        Tracing options:
        -v: Prints the expressions's AST (abstract syntax tree), which gives
@@ -935,6 +936,7 @@ VERBS
 	   mlr put put 'begin {@foo = 97} $column += @foo'.
 	   The value part is subject to type-inferencing as specified by -S/-F.
 	   May be specified more than once, e.g. -s name1=value1 -s name2=value2.
+	   Note: the value may be an environment variable, e.g. -s sequence=$SEQUENCE
 
        Tracing options:
        -v: Prints the expressions's AST (abstract syntax tree), which gives
diff --git a/doc/mlr.1 b/doc/mlr.1
index 8e009a7ef..249ca5836 100644
--- a/doc/mlr.1
+++ b/doc/mlr.1
@@ -757,6 +757,7 @@ semicolons to separate expressions.)
     mlr filter put 'begin {@foo = 97} $column += @foo'.
     The value part is subject to type-inferencing as specified by -S/-F.
     May be specified more than once, e.g. -s name1=value1 -s name2=value2.
+    Note: the value may be an environment variable, e.g. -s sequence=$SEQUENCE
 
 Tracing options:
 -v: Prints the expressions's AST (abstract syntax tree), which gives
@@ -1226,6 +1227,7 @@ semicolons to separate expressions.)
     mlr put put 'begin {@foo = 97} $column += @foo'.
     The value part is subject to type-inferencing as specified by -S/-F.
     May be specified more than once, e.g. -s name1=value1 -s name2=value2.
+    Note: the value may be an environment variable, e.g. -s sequence=$SEQUENCE
 
 Tracing options:
 -v: Prints the expressions's AST (abstract syntax tree), which gives
diff --git a/doc/reference-dsl.html b/doc/reference-dsl.html
index 2103a2bd3..fa46e1a6e 100644
--- a/doc/reference-dsl.html
+++ b/doc/reference-dsl.html
@@ -2025,7 +2025,7 @@ subsequent assignments are done unconditionally:
 <pre>
 $ mlr put '$x &gt; 0.0; $y = log10($x); $z = sqrt($y)' data/put-gating-example-1.dkvp
 x=-1,y=nan,z=nan
-x=0,y=-inf,z=-nan
+x=0,y=-inf,z=nan
 x=1,y=0.000000,z=0.000000
 x=2,y=0.301030,z=0.548662
 x=3,y=0.477121,z=0.690740
diff --git a/doc/reference-verbs.html b/doc/reference-verbs.html
index cfb199627..059f9309a 100644
--- a/doc/reference-verbs.html
+++ b/doc/reference-verbs.html
@@ -70,6 +70,7 @@ pageTracker._trackPageview();
 &bull;&nbsp;<a href="#cat">cat</a><br/>
 &bull;&nbsp;<a href="#check">check</a><br/>
 &bull;&nbsp;<a href="#clean-whitespace">clean-whitespace</a><br/>
+&bull;&nbsp;<a href="#count">count</a><br/>
 &bull;&nbsp;<a href="#count-distinct">count-distinct</a><br/>
 &bull;&nbsp;<a href="#count-similar">count-similar</a><br/>
 &bull;&nbsp;<a href="#cut">cut</a><br/>
@@ -586,6 +587,82 @@ $ mlr --icsv --ojson clean-whitespace data/clean-whitespace.csv
 <li/> <a href="./reference-verbs.html/#clean_whitespace">clean_whitespace</a>
 </ul>
 
+</div>
+<!-- ================================================================ -->
+<a id="count"/><h1>count</h1>
+<button style="font-weight:bold;color:maroon;border:0" padding=0 onclick="bodyToggler.toggle('body_section_toggle_count');" href="javascript:;">Toggle section visibility</button>
+<div id="body_section_toggle_count" style="display: block">
+
+<p/>
+<div class="pokipanel">
+<pre>
+$ mlr count --help
+Usage: mlr count [options]
+Prints number of records, optionally grouped by distinct values for specified field names.
+
+Options:
+-g {a,b,c}    Field names for distinct count.
+-n            Show only the number of distinct values. Not compatible with -u.
+-o {name}     Field name for output count. Default "count".
+</pre>
+</div>
+<p/>
+
+<p/>
+<div class="pokipanel">
+<pre>
+$ mlr count data/medium
+count=10000
+</pre>
+</div>
+<p/>
+
+<p/>
+<div class="pokipanel">
+<pre>
+$ mlr count -g a data/medium
+a=pan,count=2081
+a=eks,count=1965
+a=wye,count=1966
+a=zee,count=2047
+a=hat,count=1941
+</pre>
+</div>
+<p/>
+
+<p/>
+<div class="pokipanel">
+<pre>
+$ mlr count -g a,b data/medium
+a=pan,b=pan,count=427
+a=eks,b=pan,count=371
+a=wye,b=wye,count=377
+a=eks,b=wye,count=407
+a=wye,b=pan,count=392
+a=zee,b=pan,count=389
+a=eks,b=zee,count=357
+a=zee,b=wye,count=455
+a=hat,b=wye,count=423
+a=pan,b=wye,count=395
+a=zee,b=eks,count=391
+a=hat,b=zee,count=385
+a=hat,b=eks,count=389
+a=wye,b=hat,count=426
+a=pan,b=eks,count=429
+a=eks,b=eks,count=413
+a=hat,b=hat,count=381
+a=hat,b=pan,count=363
+a=zee,b=zee,count=403
+a=pan,b=hat,count=417
+a=pan,b=zee,count=413
+a=zee,b=hat,count=409
+a=wye,b=zee,count=385
+a=eks,b=hat,count=417
+a=wye,b=eks,count=386
+</pre>
+</div>
+<p/>
+
 </div>
 <!-- ================================================================ -->
 <a id="count-distinct"/><h1>count-distinct</h1>
@@ -1020,6 +1097,7 @@ semicolons to separate expressions.)
     mlr filter put 'begin {@foo = 97} $column += @foo'.
     The value part is subject to type-inferencing as specified by -S/-F.
     May be specified more than once, e.g. -s name1=value1 -s name2=value2.
+    Note: the value may be an environment variable, e.g. -s sequence=$SEQUENCE
 
 Tracing options:
 -v: Prints the expressions's AST (abstract syntax tree), which gives
@@ -2403,6 +2481,7 @@ semicolons to separate expressions.)
     mlr put put 'begin {@foo = 97} $column += @foo'.
     The value part is subject to type-inferencing as specified by -S/-F.
     May be specified more than once, e.g. -s name1=value1 -s name2=value2.
+    Note: the value may be an environment variable, e.g. -s sequence=$SEQUENCE
 
 Tracing options:
 -v: Prints the expressions's AST (abstract syntax tree), which gives
@@ -3968,7 +4047,7 @@ Options:
 <div class="pokipanel">
 <pre>
 $ wc -l data/colored-shapes.dkvp
-10078 data/colored-shapes.dkvp
+   10078 data/colored-shapes.dkvp
 </pre>
 </div>
 <p/>
@@ -4140,7 +4219,7 @@ color=purple,shape=square,flag=0
 <div class="pokipanel">
 <pre>
 $ wc -l data/repeats.dkvp
-57 data/repeats.dkvp
+      57 data/repeats.dkvp
 </pre>
 </div>
 <p/>