From 9c29f0cef96ea551a4d72a7d53b1615430abaeb3 Mon Sep 17 00:00:00 2001
From: John Kerl <kerl.john.r@gmail.com>
Date: Fri, 4 Feb 2022 22:43:33 -0500
Subject: [PATCH] Multiple on-line-help issues from #908 (#913)

* Populate help strings for systime, systimeint, and uptime DSL functions

* Extend help strings for joink, joinv, and joinkv

* Expand on-line help for ssub/sub/gsub

* doc artifacts
---
 docs/src/csv-with-and-without-headers.md      |  4 +-
 docs/src/manpage.md                           | 30 ++++++++----
 docs/src/manpage.txt                          | 30 ++++++++----
 docs/src/reference-dsl-builtin-functions.md   | 28 ++++++++---
 .../pkg/dsl/cst/builtin_function_manager.go   | 46 +++++++++++++------
 man/manpage.txt                               | 30 ++++++++----
 man/mlr.1                                     | 32 +++++++++----
 7 files changed, 144 insertions(+), 56 deletions(-)

diff --git a/docs/src/csv-with-and-without-headers.md b/docs/src/csv-with-and-without-headers.md
index 031e54443..944255e55 100644
--- a/docs/src/csv-with-and-without-headers.md
+++ b/docs/src/csv-with-and-without-headers.md
@@ -238,7 +238,7 @@ a,b,c
 <pre class="pre-non-highlight-in-pair">
 a,b,c
 1,2,3
-4,5
+4,5,
 6,7,8,9
 </pre>
 
@@ -255,7 +255,7 @@ or, more simply,
 <pre class="pre-non-highlight-in-pair">
 a,b,c
 1,2,3
-4,5
+4,5,
 6,7,8,9
 </pre>
 
diff --git a/docs/src/manpage.md b/docs/src/manpage.md
index 55b50c5ac..a59a96a5c 100644
--- a/docs/src/manpage.md
+++ b/docs/src/manpage.md
@@ -2223,6 +2223,12 @@ FUNCTIONS FOR FILTER/PUT
 
    gsub
         (class=string #args=3) '$name=gsub($name, "old", "new")' (replace all).
+       Examples:
+       gsub("ababab", "ab", "XY") gives "XYXYXY"
+       gsub("abc.def", ".", "X") gives "XXXXXXX"
+       gsub("abc.def", "\.", "X") gives "abcXdef"
+       gsub("abcdefg", "[ce]", "X") gives "abXdXfg"
+       gsub("prefix4529:suffix8567", "(....ix)([0-9]+)", "[\1 : \2]") gives "[prefix : 4529]:[suffix : 8567]"
 
    haskey
         (class=collections #args=2) True/false if map has/hasn't key, e.g. 'haskey($*, "a")' or 'haskey(mymap, mykey)', or true/false if array index is in bounds / out of bounds. Error if 1st argument is not a map or array. Note -n..-1 alias to 1..n in Miller arrays.
@@ -2303,19 +2309,19 @@ FUNCTIONS FOR FILTER/PUT
         (class=typing #args=1) True if field is present with string (including empty-string) value
 
    joink
-        (class=conversion #args=2) Makes string from map/array keys.
+        (class=conversion #args=2) Makes string from map/array keys. First argument is map/array; second is separator string.
        Examples:
        joink({"a":3,"b":4,"c":5}, ",") = "a,b,c".
        joink([1,2,3], ",") = "1,2,3".
 
    joinkv
-        (class=conversion #args=3) Makes string from map/array key-value pairs.
+        (class=conversion #args=3) Makes string from map/array key-value pairs. First argument is map/array; second is pair-separator string; third is field-separator string. Mnemonic: the "=" comes before the "," in the output and in the arguments to joinkv.
        Examples:
        joinkv([3,4,5], "=", ",") = "1=3,2=4,3=5"
-       joinkv({"a":3,"b":4,"c":5}, "=", ",") = "a=3,b=4,c=5"
+       joinkv({"a":3,"b":4,"c":5}, ":", ";") = "a:3;b:4;c:5"
 
    joinv
-        (class=conversion #args=2) Makes string from map/array values.
+        (class=conversion #args=2) Makes string from map/array values. First argument is map/array; second is separator string.
        Examples:
        joinv([3,4,5], ",") = "3,4,5"
        joinv({"a":3,"b":4,"c":5}, ",") = "3,4,5"
@@ -2519,6 +2525,8 @@ FUNCTIONS FOR FILTER/PUT
 
    ssub
         (class=string #args=3) Like sub but does no regexing. No characters are special.
+       Example:
+       ssub("abc.def", ".", "X") gives "abcXdef"
 
    strftime
         (class=time #args=2) Formats seconds since the epoch as timestamp. Format strings are as in the C library (please see "man strftime" on your system), with the Miller-specific addition of "%1S" through "%9S" which format the seconds with 1 through 9 decimal places, respectively. ("%S" uses no decimal places.) See also strftime_local.
@@ -2560,6 +2568,12 @@ FUNCTIONS FOR FILTER/PUT
 
    sub
         (class=string #args=3) '$name=sub($name, "old", "new")' (replace once).
+       Examples:
+       sub("ababab", "ab", "XY") gives "XYabab"
+       sub("abc.def", ".", "X") gives "Xbc.def"
+       sub("abc.def", "\.", "X") gives "abcXdef"
+       sub("abcdefg", "[ce]", "X") gives "abXdefg"
+       sub("prefix4529:suffix8567", "suffix([0-9]+)", "name\1") gives "prefix4529:name8567"
 
    substr
         (class=string #args=3) substr is an alias for substr0. See also substr1. Miller is generally 1-up with all array and string indices, but, this is a backward-compatibility issue with Miller 5 and below. Arrays are new in Miller 6; the substr function is older.
@@ -2574,10 +2588,10 @@ FUNCTIONS FOR FILTER/PUT
         (class=system #args=1) Run command string, yielding its stdout minus final carriage return.
 
    systime
-        (class=time #args=0) help string will go here
+        (class=time #args=0) Returns the system time in floating-point seconds since the epoch.
 
    systimeint
-        (class=time #args=0) help string will go here
+        (class=time #args=0) Returns the system time in integer seconds since the epoch.
 
    tan
         (class=math #args=1) Trigonometric tangent.
@@ -2617,7 +2631,7 @@ FUNCTIONS FOR FILTER/PUT
        is_error(unformatx("{}h{}m{}s", "3:47:22")) gives true.
 
    uptime
-        (class=time #args=0) help string will go here
+        (class=time #args=0) Returns the time in floating-point seconds since the current Miller program was started.
 
    urand
         (class=math #args=0) Floating-point numbers uniformly distributed on the unit interval.
@@ -3134,5 +3148,5 @@ SEE ALSO
 
 
 
-                                  2022-02-01                         MILLER(1)
+                                  2022-02-05                         MILLER(1)
 </pre>
diff --git a/docs/src/manpage.txt b/docs/src/manpage.txt
index b06bf09b9..a595e2ba2 100644
--- a/docs/src/manpage.txt
+++ b/docs/src/manpage.txt
@@ -2202,6 +2202,12 @@ FUNCTIONS FOR FILTER/PUT
 
    gsub
         (class=string #args=3) '$name=gsub($name, "old", "new")' (replace all).
+       Examples:
+       gsub("ababab", "ab", "XY") gives "XYXYXY"
+       gsub("abc.def", ".", "X") gives "XXXXXXX"
+       gsub("abc.def", "\.", "X") gives "abcXdef"
+       gsub("abcdefg", "[ce]", "X") gives "abXdXfg"
+       gsub("prefix4529:suffix8567", "(....ix)([0-9]+)", "[\1 : \2]") gives "[prefix : 4529]:[suffix : 8567]"
 
    haskey
         (class=collections #args=2) True/false if map has/hasn't key, e.g. 'haskey($*, "a")' or 'haskey(mymap, mykey)', or true/false if array index is in bounds / out of bounds. Error if 1st argument is not a map or array. Note -n..-1 alias to 1..n in Miller arrays.
@@ -2282,19 +2288,19 @@ FUNCTIONS FOR FILTER/PUT
         (class=typing #args=1) True if field is present with string (including empty-string) value
 
    joink
-        (class=conversion #args=2) Makes string from map/array keys.
+        (class=conversion #args=2) Makes string from map/array keys. First argument is map/array; second is separator string.
        Examples:
        joink({"a":3,"b":4,"c":5}, ",") = "a,b,c".
        joink([1,2,3], ",") = "1,2,3".
 
    joinkv
-        (class=conversion #args=3) Makes string from map/array key-value pairs.
+        (class=conversion #args=3) Makes string from map/array key-value pairs. First argument is map/array; second is pair-separator string; third is field-separator string. Mnemonic: the "=" comes before the "," in the output and in the arguments to joinkv.
        Examples:
        joinkv([3,4,5], "=", ",") = "1=3,2=4,3=5"
-       joinkv({"a":3,"b":4,"c":5}, "=", ",") = "a=3,b=4,c=5"
+       joinkv({"a":3,"b":4,"c":5}, ":", ";") = "a:3;b:4;c:5"
 
    joinv
-        (class=conversion #args=2) Makes string from map/array values.
+        (class=conversion #args=2) Makes string from map/array values. First argument is map/array; second is separator string.
        Examples:
        joinv([3,4,5], ",") = "3,4,5"
        joinv({"a":3,"b":4,"c":5}, ",") = "3,4,5"
@@ -2498,6 +2504,8 @@ FUNCTIONS FOR FILTER/PUT
 
    ssub
         (class=string #args=3) Like sub but does no regexing. No characters are special.
+       Example:
+       ssub("abc.def", ".", "X") gives "abcXdef"
 
    strftime
         (class=time #args=2) Formats seconds since the epoch as timestamp. Format strings are as in the C library (please see "man strftime" on your system), with the Miller-specific addition of "%1S" through "%9S" which format the seconds with 1 through 9 decimal places, respectively. ("%S" uses no decimal places.) See also strftime_local.
@@ -2539,6 +2547,12 @@ FUNCTIONS FOR FILTER/PUT
 
    sub
         (class=string #args=3) '$name=sub($name, "old", "new")' (replace once).
+       Examples:
+       sub("ababab", "ab", "XY") gives "XYabab"
+       sub("abc.def", ".", "X") gives "Xbc.def"
+       sub("abc.def", "\.", "X") gives "abcXdef"
+       sub("abcdefg", "[ce]", "X") gives "abXdefg"
+       sub("prefix4529:suffix8567", "suffix([0-9]+)", "name\1") gives "prefix4529:name8567"
 
    substr
         (class=string #args=3) substr is an alias for substr0. See also substr1. Miller is generally 1-up with all array and string indices, but, this is a backward-compatibility issue with Miller 5 and below. Arrays are new in Miller 6; the substr function is older.
@@ -2553,10 +2567,10 @@ FUNCTIONS FOR FILTER/PUT
         (class=system #args=1) Run command string, yielding its stdout minus final carriage return.
 
    systime
-        (class=time #args=0) help string will go here
+        (class=time #args=0) Returns the system time in floating-point seconds since the epoch.
 
    systimeint
-        (class=time #args=0) help string will go here
+        (class=time #args=0) Returns the system time in integer seconds since the epoch.
 
    tan
         (class=math #args=1) Trigonometric tangent.
@@ -2596,7 +2610,7 @@ FUNCTIONS FOR FILTER/PUT
        is_error(unformatx("{}h{}m{}s", "3:47:22")) gives true.
 
    uptime
-        (class=time #args=0) help string will go here
+        (class=time #args=0) Returns the time in floating-point seconds since the current Miller program was started.
 
    urand
         (class=math #args=0) Floating-point numbers uniformly distributed on the unit interval.
@@ -3113,4 +3127,4 @@ SEE ALSO
 
 
 
-                                  2022-02-01                         MILLER(1)
+                                  2022-02-05                         MILLER(1)
diff --git a/docs/src/reference-dsl-builtin-functions.md b/docs/src/reference-dsl-builtin-functions.md
index d8ea5c39e..8eef038d8 100644
--- a/docs/src/reference-dsl-builtin-functions.md
+++ b/docs/src/reference-dsl-builtin-functions.md
@@ -505,7 +505,7 @@ int  (class=conversion #args=1) Convert int/float/bool/string to int.
 
 ### joink
 <pre class="pre-non-highlight-non-pair">
-joink  (class=conversion #args=2) Makes string from map/array keys.
+joink  (class=conversion #args=2) Makes string from map/array keys. First argument is map/array; second is separator string.
 Examples:
 joink({"a":3,"b":4,"c":5}, ",") = "a,b,c".
 joink([1,2,3], ",") = "1,2,3".
@@ -514,16 +514,16 @@ joink([1,2,3], ",") = "1,2,3".
 
 ### joinkv
 <pre class="pre-non-highlight-non-pair">
-joinkv  (class=conversion #args=3) Makes string from map/array key-value pairs.
+joinkv  (class=conversion #args=3) Makes string from map/array key-value pairs. First argument is map/array; second is pair-separator string; third is field-separator string. Mnemonic: the "=" comes before the "," in the output and in the arguments to joinkv.
 Examples:
 joinkv([3,4,5], "=", ",") = "1=3,2=4,3=5"
-joinkv({"a":3,"b":4,"c":5}, "=", ",") = "a=3,b=4,c=5"
+joinkv({"a":3,"b":4,"c":5}, ":", ";") = "a:3;b:4;c:5"
 </pre>
 
 
 ### joinv
 <pre class="pre-non-highlight-non-pair">
-joinv  (class=conversion #args=2) Makes string from map/array values.
+joinv  (class=conversion #args=2) Makes string from map/array values. First argument is map/array; second is separator string.
 Examples:
 joinv([3,4,5], ",") = "3,4,5"
 joinv({"a":3,"b":4,"c":5}, ",") = "3,4,5"
@@ -940,6 +940,12 @@ format("{}:{}:{}", 1,2,3,4) gives "1:2:3".
 ### gsub
 <pre class="pre-non-highlight-non-pair">
 gsub  (class=string #args=3) '$name=gsub($name, "old", "new")' (replace all).
+Examples:
+gsub("ababab", "ab", "XY") gives "XYXYXY"
+gsub("abc.def", ".", "X") gives "XXXXXXX"
+gsub("abc.def", "\.", "X") gives "abcXdef"
+gsub("abcdefg", "[ce]", "X") gives "abXdXfg"
+gsub("prefix4529:suffix8567", "(....ix)([0-9]+)", "[\1 : \2]") gives "[prefix : 4529]:[suffix : 8567]"
 </pre>
 
 
@@ -970,6 +976,8 @@ rstrip  (class=string #args=1) Strip trailing whitespace from string.
 ### ssub
 <pre class="pre-non-highlight-non-pair">
 ssub  (class=string #args=3) Like sub but does no regexing. No characters are special.
+Example:
+ssub("abc.def", ".", "X") gives "abcXdef"
 </pre>
 
 
@@ -988,6 +996,12 @@ strlen  (class=string #args=1) String length.
 ### sub
 <pre class="pre-non-highlight-non-pair">
 sub  (class=string #args=3) '$name=sub($name, "old", "new")' (replace once).
+Examples:
+sub("ababab", "ab", "XY") gives "XYabab"
+sub("abc.def", ".", "X") gives "Xbc.def"
+sub("abc.def", "\.", "X") gives "abcXdef"
+sub("abcdefg", "[ce]", "X") gives "abXdefg"
+sub("prefix4529:suffix8567", "suffix([0-9]+)", "name\1") gives "prefix4529:name8567"
 </pre>
 
 
@@ -1246,19 +1260,19 @@ strptime_local("2015-08-28 13:33:21",     "%Y-%m-%d %H:%M:%S", "Asia/Istanbul")
 
 ### systime
 <pre class="pre-non-highlight-non-pair">
-systime  (class=time #args=0) help string will go here
+systime  (class=time #args=0) Returns the system time in floating-point seconds since the epoch.
 </pre>
 
 
 ### systimeint
 <pre class="pre-non-highlight-non-pair">
-systimeint  (class=time #args=0) help string will go here
+systimeint  (class=time #args=0) Returns the system time in integer seconds since the epoch.
 </pre>
 
 
 ### uptime
 <pre class="pre-non-highlight-non-pair">
-uptime  (class=time #args=0) help string will go here
+uptime  (class=time #args=0) Returns the time in floating-point seconds since the current Miller program was started.
 </pre>
 
 ## Typing functions
diff --git a/internal/pkg/dsl/cst/builtin_function_manager.go b/internal/pkg/dsl/cst/builtin_function_manager.go
index 4e908ff6c..de7439250 100644
--- a/internal/pkg/dsl/cst/builtin_function_manager.go
+++ b/internal/pkg/dsl/cst/builtin_function_manager.go
@@ -403,13 +403,6 @@ func makeBuiltinFunctionLookupTable() []BuiltinFunctionInfo {
 			unaryFunc: bifs.BIF_collapse_whitespace,
 		},
 
-		{
-			name:        "gsub",
-			class:       FUNC_CLASS_STRING,
-			help:        `'$name=gsub($name, "old", "new")' (replace all).`,
-			ternaryFunc: bifs.BIF_gsub,
-		},
-
 		{
 			name:      "lstrip",
 			class:     FUNC_CLASS_STRING,
@@ -457,6 +450,9 @@ func makeBuiltinFunctionLookupTable() []BuiltinFunctionInfo {
 			class:       FUNC_CLASS_STRING,
 			help:        `Like sub but does no regexing. No characters are special.`,
 			ternaryFunc: bifs.BIF_ssub,
+			examples: []string{
+				`ssub("abc.def", ".", "X") gives "abcXdef"`,
+			},
 		},
 
 		{
@@ -464,6 +460,27 @@ func makeBuiltinFunctionLookupTable() []BuiltinFunctionInfo {
 			class:       FUNC_CLASS_STRING,
 			help:        `'$name=sub($name, "old", "new")' (replace once).`,
 			ternaryFunc: bifs.BIF_sub,
+			examples: []string{
+				`sub("ababab", "ab", "XY") gives "XYabab"`,
+				`sub("abc.def", ".", "X") gives "Xbc.def"`,
+				`sub("abc.def", "\.", "X") gives "abcXdef"`,
+				`sub("abcdefg", "[ce]", "X") gives "abXdefg"`,
+				`sub("prefix4529:suffix8567", "suffix([0-9]+)", "name\1") gives "prefix4529:name8567"`,
+			},
+		},
+
+		{
+			name:        "gsub",
+			class:       FUNC_CLASS_STRING,
+			help:        `'$name=gsub($name, "old", "new")' (replace all).`,
+			ternaryFunc: bifs.BIF_gsub,
+			examples: []string{
+				`gsub("ababab", "ab", "XY") gives "XYXYXY"`,
+				`gsub("abc.def", ".", "X") gives "XXXXXXX"`,
+				`gsub("abc.def", "\.", "X") gives "abcXdef"`,
+				`gsub("abcdefg", "[ce]", "X") gives "abXdXfg"`,
+				`gsub("prefix4529:suffix8567", "(....ix)([0-9]+)", "[\1 : \2]") gives "[prefix : 4529]:[suffix : 8567]"`,
+			},
 		},
 
 		{
@@ -1081,21 +1098,21 @@ strftime_local.`,
 		{
 			name:     "systime",
 			class:    FUNC_CLASS_TIME,
-			help:     "help string will go here",
+			help:     "Returns the system time in floating-point seconds since the epoch.",
 			zaryFunc: bifs.BIF_systime,
 		},
 
 		{
 			name:     "systimeint",
 			class:    FUNC_CLASS_TIME,
-			help:     "help string will go here",
+			help:     "Returns the system time in integer seconds since the epoch.",
 			zaryFunc: bifs.BIF_systimeint,
 		},
 
 		{
 			name:     "uptime",
 			class:    FUNC_CLASS_TIME,
-			help:     "help string will go here",
+			help:     "Returns the time in floating-point seconds since the current Miller program was started.",
 			zaryFunc: bifs.BIF_uptime,
 		},
 
@@ -1417,7 +1434,7 @@ strftime_local.`,
 		{
 			name:  "joink",
 			class: FUNC_CLASS_CONVERSION,
-			help:  `Makes string from map/array keys.`,
+			help:  `Makes string from map/array keys. First argument is map/array; second is separator string.`,
 			examples: []string{
 				`joink({"a":3,"b":4,"c":5}, ",") = "a,b,c".`,
 				`joink([1,2,3], ",") = "1,2,3".`,
@@ -1428,7 +1445,7 @@ strftime_local.`,
 		{
 			name:  "joinv",
 			class: FUNC_CLASS_CONVERSION,
-			help:  `Makes string from map/array values.`,
+			help:  `Makes string from map/array values. First argument is map/array; second is separator string.`,
 			examples: []string{
 				`joinv([3,4,5], ",") = "3,4,5"`,
 				`joinv({"a":3,"b":4,"c":5}, ",") = "3,4,5"`,
@@ -1439,10 +1456,11 @@ strftime_local.`,
 		{
 			name:  "joinkv",
 			class: FUNC_CLASS_CONVERSION,
-			help:  `Makes string from map/array key-value pairs.`,
+			help: `Makes string from map/array key-value pairs. First argument is map/array;
+second is pair-separator string; third is field-separator string. Mnemonic: the "=" comes before the "," in the output and in the arguments to joinkv.`,
 			examples: []string{
 				`joinkv([3,4,5], "=", ",") = "1=3,2=4,3=5"`,
-				`joinkv({"a":3,"b":4,"c":5}, "=", ",") = "a=3,b=4,c=5"`,
+				`joinkv({"a":3,"b":4,"c":5}, ":", ";") = "a:3;b:4;c:5"`,
 			},
 			ternaryFunc: bifs.BIF_joinkv,
 		},
diff --git a/man/manpage.txt b/man/manpage.txt
index b06bf09b9..a595e2ba2 100644
--- a/man/manpage.txt
+++ b/man/manpage.txt
@@ -2202,6 +2202,12 @@ FUNCTIONS FOR FILTER/PUT
 
    gsub
         (class=string #args=3) '$name=gsub($name, "old", "new")' (replace all).
+       Examples:
+       gsub("ababab", "ab", "XY") gives "XYXYXY"
+       gsub("abc.def", ".", "X") gives "XXXXXXX"
+       gsub("abc.def", "\.", "X") gives "abcXdef"
+       gsub("abcdefg", "[ce]", "X") gives "abXdXfg"
+       gsub("prefix4529:suffix8567", "(....ix)([0-9]+)", "[\1 : \2]") gives "[prefix : 4529]:[suffix : 8567]"
 
    haskey
         (class=collections #args=2) True/false if map has/hasn't key, e.g. 'haskey($*, "a")' or 'haskey(mymap, mykey)', or true/false if array index is in bounds / out of bounds. Error if 1st argument is not a map or array. Note -n..-1 alias to 1..n in Miller arrays.
@@ -2282,19 +2288,19 @@ FUNCTIONS FOR FILTER/PUT
         (class=typing #args=1) True if field is present with string (including empty-string) value
 
    joink
-        (class=conversion #args=2) Makes string from map/array keys.
+        (class=conversion #args=2) Makes string from map/array keys. First argument is map/array; second is separator string.
        Examples:
        joink({"a":3,"b":4,"c":5}, ",") = "a,b,c".
        joink([1,2,3], ",") = "1,2,3".
 
    joinkv
-        (class=conversion #args=3) Makes string from map/array key-value pairs.
+        (class=conversion #args=3) Makes string from map/array key-value pairs. First argument is map/array; second is pair-separator string; third is field-separator string. Mnemonic: the "=" comes before the "," in the output and in the arguments to joinkv.
        Examples:
        joinkv([3,4,5], "=", ",") = "1=3,2=4,3=5"
-       joinkv({"a":3,"b":4,"c":5}, "=", ",") = "a=3,b=4,c=5"
+       joinkv({"a":3,"b":4,"c":5}, ":", ";") = "a:3;b:4;c:5"
 
    joinv
-        (class=conversion #args=2) Makes string from map/array values.
+        (class=conversion #args=2) Makes string from map/array values. First argument is map/array; second is separator string.
        Examples:
        joinv([3,4,5], ",") = "3,4,5"
        joinv({"a":3,"b":4,"c":5}, ",") = "3,4,5"
@@ -2498,6 +2504,8 @@ FUNCTIONS FOR FILTER/PUT
 
    ssub
         (class=string #args=3) Like sub but does no regexing. No characters are special.
+       Example:
+       ssub("abc.def", ".", "X") gives "abcXdef"
 
    strftime
         (class=time #args=2) Formats seconds since the epoch as timestamp. Format strings are as in the C library (please see "man strftime" on your system), with the Miller-specific addition of "%1S" through "%9S" which format the seconds with 1 through 9 decimal places, respectively. ("%S" uses no decimal places.) See also strftime_local.
@@ -2539,6 +2547,12 @@ FUNCTIONS FOR FILTER/PUT
 
    sub
         (class=string #args=3) '$name=sub($name, "old", "new")' (replace once).
+       Examples:
+       sub("ababab", "ab", "XY") gives "XYabab"
+       sub("abc.def", ".", "X") gives "Xbc.def"
+       sub("abc.def", "\.", "X") gives "abcXdef"
+       sub("abcdefg", "[ce]", "X") gives "abXdefg"
+       sub("prefix4529:suffix8567", "suffix([0-9]+)", "name\1") gives "prefix4529:name8567"
 
    substr
         (class=string #args=3) substr is an alias for substr0. See also substr1. Miller is generally 1-up with all array and string indices, but, this is a backward-compatibility issue with Miller 5 and below. Arrays are new in Miller 6; the substr function is older.
@@ -2553,10 +2567,10 @@ FUNCTIONS FOR FILTER/PUT
         (class=system #args=1) Run command string, yielding its stdout minus final carriage return.
 
    systime
-        (class=time #args=0) help string will go here
+        (class=time #args=0) Returns the system time in floating-point seconds since the epoch.
 
    systimeint
-        (class=time #args=0) help string will go here
+        (class=time #args=0) Returns the system time in integer seconds since the epoch.
 
    tan
         (class=math #args=1) Trigonometric tangent.
@@ -2596,7 +2610,7 @@ FUNCTIONS FOR FILTER/PUT
        is_error(unformatx("{}h{}m{}s", "3:47:22")) gives true.
 
    uptime
-        (class=time #args=0) help string will go here
+        (class=time #args=0) Returns the time in floating-point seconds since the current Miller program was started.
 
    urand
         (class=math #args=0) Floating-point numbers uniformly distributed on the unit interval.
@@ -3113,4 +3127,4 @@ SEE ALSO
 
 
 
-                                  2022-02-01                         MILLER(1)
+                                  2022-02-05                         MILLER(1)
diff --git a/man/mlr.1 b/man/mlr.1
index c1ad0f6bf..a92c084be 100644
--- a/man/mlr.1
+++ b/man/mlr.1
@@ -2,12 +2,12 @@
 .\"     Title: mlr
 .\"    Author: [see the "AUTHOR" section]
 .\" Generator: ./mkman.rb
-.\"      Date: 2022-02-01
+.\"      Date: 2022-02-05
 .\"    Manual: \ \&
 .\"    Source: \ \&
 .\"  Language: English
 .\"
-.TH "MILLER" "1" "2022-02-01" "\ \&" "\ \&"
+.TH "MILLER" "1" "2022-02-05" "\ \&" "\ \&"
 .\" -----------------------------------------------------------------
 .\" * Portability definitions
 .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -3099,6 +3099,12 @@ gmt2sec("2001-02-03T04:05:06Z") = 981173106
 .\}
 .nf
  (class=string #args=3) '$name=gsub($name, "old", "new")' (replace all).
+Examples:
+gsub("ababab", "ab", "XY") gives "XYXYXY"
+gsub("abc.def", ".", "X") gives "XXXXXXX"
+gsub("abc.def", "\e.", "X") gives "abcXdef"
+gsub("abcdefg", "[ce]", "X") gives "abXdXfg"
+gsub("prefix4529:suffix8567", "(....ix)([0-9]+)", "[\e1 : \e2]") gives "[prefix : 4529]:[suffix : 8567]"
 .fi
 .if n \{\
 .RE
@@ -3341,7 +3347,7 @@ gmt2sec("2001-02-03T04:05:06Z") = 981173106
 .RS 0
 .\}
 .nf
- (class=conversion #args=2) Makes string from map/array keys.
+ (class=conversion #args=2) Makes string from map/array keys. First argument is map/array; second is separator string.
 Examples:
 joink({"a":3,"b":4,"c":5}, ",") = "a,b,c".
 joink([1,2,3], ",") = "1,2,3".
@@ -3353,10 +3359,10 @@ joink([1,2,3], ",") = "1,2,3".
 .RS 0
 .\}
 .nf
- (class=conversion #args=3) Makes string from map/array key-value pairs.
+ (class=conversion #args=3) Makes string from map/array key-value pairs. First argument is map/array; second is pair-separator string; third is field-separator string. Mnemonic: the "=" comes before the "," in the output and in the arguments to joinkv.
 Examples:
 joinkv([3,4,5], "=", ",") = "1=3,2=4,3=5"
-joinkv({"a":3,"b":4,"c":5}, "=", ",") = "a=3,b=4,c=5"
+joinkv({"a":3,"b":4,"c":5}, ":", ";") = "a:3;b:4;c:5"
 .fi
 .if n \{\
 .RE
@@ -3365,7 +3371,7 @@ joinkv({"a":3,"b":4,"c":5}, "=", ",") = "a=3,b=4,c=5"
 .RS 0
 .\}
 .nf
- (class=conversion #args=2) Makes string from map/array values.
+ (class=conversion #args=2) Makes string from map/array values. First argument is map/array; second is separator string.
 Examples:
 joinv([3,4,5], ",") = "3,4,5"
 joinv({"a":3,"b":4,"c":5}, ",") = "3,4,5"
@@ -3887,6 +3893,8 @@ splitnvx("3,4,5", ",") = {"1":"3","2":"4","3":"5"}
 .\}
 .nf
  (class=string #args=3) Like sub but does no regexing. No characters are special.
+Example:
+ssub("abc.def", ".", "X") gives "abcXdef"
 .fi
 .if n \{\
 .RE
@@ -3976,6 +3984,12 @@ strptime_local("2015-08-28 13:33:21",     "%Y-%m-%d %H:%M:%S", "Asia/Istanbul")
 .\}
 .nf
  (class=string #args=3) '$name=sub($name, "old", "new")' (replace once).
+Examples:
+sub("ababab", "ab", "XY") gives "XYabab"
+sub("abc.def", ".", "X") gives "Xbc.def"
+sub("abc.def", "\e.", "X") gives "abcXdef"
+sub("abcdefg", "[ce]", "X") gives "abXdefg"
+sub("prefix4529:suffix8567", "suffix([0-9]+)", "name\e1") gives "prefix4529:name8567"
 .fi
 .if n \{\
 .RE
@@ -4020,7 +4034,7 @@ strptime_local("2015-08-28 13:33:21",     "%Y-%m-%d %H:%M:%S", "Asia/Istanbul")
 .RS 0
 .\}
 .nf
- (class=time #args=0) help string will go here
+ (class=time #args=0) Returns the system time in floating-point seconds since the epoch.
 .fi
 .if n \{\
 .RE
@@ -4029,7 +4043,7 @@ strptime_local("2015-08-28 13:33:21",     "%Y-%m-%d %H:%M:%S", "Asia/Istanbul")
 .RS 0
 .\}
 .nf
- (class=time #args=0) help string will go here
+ (class=time #args=0) Returns the system time in integer seconds since the epoch.
 .fi
 .if n \{\
 .RE
@@ -4129,7 +4143,7 @@ is_error(unformatx("{}h{}m{}s", "3:47:22")) gives true.
 .RS 0
 .\}
 .nf
- (class=time #args=0) help string will go here
+ (class=time #args=0) Returns the time in floating-point seconds since the current Miller program was started.
 .fi
 .if n \{\
 .RE