This patch modifies crontab.5 in order to give useful
information about using eval command, which makes easier to
express environment assignments inside commands to call with
cron.

Index: cron/crontab.5
===================================================================
--- cron.orig/crontab.5
+++ cron/crontab.5
@@ -64,8 +64,8 @@ tilde(~) expansion, thus lines like
 .PP
 .in +4n
 .nf
-PATH = $HOME/bin:$PATH
-PATH = ~/bin:/usr/bin
+PATH=$HOME/bin:$PATH
+PATH=~/bin:/usr/bin
 .fi
 .in
 .PP
@@ -80,7 +80,10 @@ C=$A $B
 .in
 .PP
 There will not be any substitution for the defined variables in the
-last value.
+last value. However, with most shells you can also try e.g.,:
+.PP
+     P=PATH=/a/b/c:$PATH
+     33 22 1 2 3 eval $P && some commands
 .PP
 Several environment variables are set up automatically by the
 .IR cron (8)
@@ -367,6 +370,17 @@ the following wrapper code:
 0 4 * * Sat   [ "$(date +\e%e)" = "$(LANG=C ncal | sed \-n 's/^Sa .* \e([0\-9]\e+\e) *$/\e1/p')" ] && echo "Last Saturday" && program_to_run
 .fi
 
+.SH USING EVAL TO WRAP MISC ENVIRONMENT SETTINGS
+The following tip is kindly provided by 積丹尼 Dan Jacobson:
+.PP
+     CONTENT_TYPE="text/plain; charset=UTF-8"
+     d=eval LANG=zh_TW.UTF-8 w3m -dump
+     26 22 16 1-12 * $d https://www.ptt.cc/bbs/transgender/index.html
+.PP
+ it won't work without the eval. Saying
+ d=LANG=zh_TW.UTF-8 w3m -dump
+ will get
+ /bin/sh: LANG=zh_TW.UTF-8: command not found
 
 .SH DIAGNOSTICS
 cron requires that each entry in a crontab end in a newline character.  If the
