Change syntax of the env.clear statement.

It no longer requires an argument. The correct syntax is

  env {
     clear;
  }

6 files changed, 22 insertions, 24 deletions

diff --git a/NEWS b/NEWS
index eee1e25..4ee1ae5 100644
--- a/NEWS
+++ b/NEWS
@@ -1,4 +1,4 @@
-GNU Pies NEWS -- history of user-visible changes. 2019-06-03
+GNU Pies NEWS -- history of user-visible changes. 2019-06-06
 See the end of file for copying conditions.
 
 Please send Pies bug reports to <bug-pies@gnu.org> or
@@ -43,12 +43,12 @@ contains redirections, pipes, etc. E.g.
 The 'env' statement has been re-implemented as a compound statement.
 It can contain the following sub-statements:
 
-** clear yes
+** clear
 Clears the environment
 
 ** keep NAME
 Keeps the variable NAME when clearing the environment. Implies
-"clear yes". NAME can be a globbing pattern, in which case all
+"clear". NAME can be a globbing pattern, in which case all
 variables matching the pattern are retained.
 
 ** set "NAME=VALUE"
@@ -62,11 +62,11 @@ variables matching the pattern are unset.
 Example:
 
  env {
-   clear yes
-   keep PATH
-   keep MANPATH
-   keep "LC_*"
-   set "MANPATH=$MANPATH${MANPATH:+:}/usr/local/man"
+   clear;
+   keep PATH;
+   keep MANPATH;
+   keep "LC_*";
+   set "MANPATH=$MANPATH${MANPATH:+:}/usr/local/man";
  }
 
 * Legacy 'env' statement.
diff --git a/doc/pies.texi b/doc/pies.texi
index ccb9f0e..63064e5 100644
--- a/doc/pies.texi
+++ b/doc/pies.texi
@@ -1061,7 +1061,7 @@ The compound @code{env} statement has the following syntax:
 @example
 @group
 env @{
-   clear @var{bool};
+   clear;
    keep @var{pattern};
    set "@var{name}=@var{value}";
    unset @var{pattern};
@@ -1075,11 +1075,10 @@ modify the environment.  The @code{clear} and @code{keep} statements
 are executed first.  Then, the @code{set} and @code{unset} statements
 are applied in the order of their appearance in the configuration.
 
-@deffn {env} clear @var{bool}
-If @var{bool} is @samp{yes}, all environment variables will be cleared
-(unset).  The resulting environment will be empty, unless one or more
-@code{keep} statements are also given (see below).  The @code{clear}
-statement is always executed first.
+@deffn {env} clear
+Clears the environment by removing (unsetting) all variables, except
+those listed in @code{keep} statements, if such are given (see below).
+The @code{clear} statement is always executed first.
 @end deffn
 
 @deffn {env} keep @var{pattern}
@@ -1093,7 +1092,7 @@ environment all variables except @samp{HOME}, @samp{USER},
 @example
 @group
 env @{
-  clear yes;
+  clear;
   keep HOME;
   keep USER;
   keep PATH;
@@ -1171,7 +1170,7 @@ The modern syntax equivalent is:
 @example
 @group
 env @{
-  clear yes;
+  clear;
 @}
 @end group
 @end example
diff --git a/src/comp.c b/src/comp.c
index d9e7966..06b5772 100644
--- a/src/comp.c
+++ b/src/comp.c
diff --git a/src/pies.c b/src/pies.c
index f8525da..1f5fb8f 100644
--- a/src/pies.c
+++ b/src/pies.c
@@ -730,17 +730,16 @@ _cb_env_clear (enum grecs_callback_command cmd,
   grecs_locus_t *locus = &node->locus;
   grecs_value_t *value = node->v.value;
   struct component *comp = varptr;
-  int clear;
 
-  if (grecs_assert_node_value_type (cmd, node, GRECS_TYPE_STRING))
-    return 1;
-  if (grecs_string_convert(&clear, grecs_type_bool, value->v.string, locus))
-    return 1;
-  if (clear)
+  if (!GRECS_VALUE_EMPTY_P (value))
     {
+      grecs_error (&value->locus, 0, "%s", _("unexpected argument"));
+      return 1;
+    }
+  
   if (envop_entry_add (&comp->envop, envop_clear, NULL, NULL))
     grecs_error (locus, errno, "envop_entry_add");
-    }
+
   return 0;
 }
 
diff --git a/src/piesctl.c b/src/piesctl.c
index 390ccfc..2e35aea 100644
--- a/src/piesctl.c
+++ b/src/piesctl.c
diff --git a/tests/env.at b/tests/env.at
index 430bf10..1c595de 100644
--- a/tests/env.at
+++ b/tests/env.at
@@ -36,7 +36,7 @@ dnl #############################
 
 AT_BANNER([Environment statement])
 
-ENVTEST([clear],[clear],[clear yes;],[])
+ENVTEST([clear],[clear],[clear;],[])
 
 ENVTEST([keep],[keep],[keep "LC_*";],
 [LC_ALL="C"