# HG changeset patch
# User haftmann
# Date 1502024574 -7200
# Node ID 882abe912da90969a000e7631f4fdbd59756e004
# Parent  455ca98d9de3e7391d68c6ce3cb69242deb2c2f9
do not fall back on nbe if plain evaluation fails

diff -r 455ca98d9de3 -r 882abe912da9 NEWS
--- a/NEWS	Sat Aug 05 22:12:41 2017 +0200
+++ b/NEWS	Sun Aug 06 15:02:54 2017 +0200
@@ -116,6 +116,11 @@
 
 *** HOL ***
 
+* Command and antiquotation "value" with modified default strategy:
+terms without free variables are always evaluated using plain evaluation
+only, with no fallback on normalization by evaluation.
+Minor INCOMPATIBILITY.
+
 * Notions of squarefreeness, n-th powers, and prime powers in
 HOL-Computational_Algebra and HOL-Number_Theory.
 
diff -r 455ca98d9de3 -r 882abe912da9 src/HOL/Tools/value_command.ML
--- a/src/HOL/Tools/value_command.ML	Sat Aug 05 22:12:41 2017 +0200
+++ b/src/HOL/Tools/value_command.ML	Sun Aug 06 15:02:54 2017 +0200
@@ -17,9 +17,7 @@
 
 fun default_value ctxt t =
   if null (Term.add_frees t [])
-  then case try (Code_Evaluation.dynamic_value_strict ctxt) t of
-    SOME t' => t'
-  | NONE => Nbe.dynamic_value ctxt t
+  then Code_Evaluation.dynamic_value_strict ctxt t
   else Nbe.dynamic_value ctxt t;
 
 structure Evaluator = Theory_Data
diff -r 455ca98d9de3 -r 882abe912da9 src/HOL/ex/Adhoc_Overloading_Examples.thy
--- a/src/HOL/ex/Adhoc_Overloading_Examples.thy	Sat Aug 05 22:12:41 2017 +0200
+++ b/src/HOL/ex/Adhoc_Overloading_Examples.thy	Sun Aug 06 15:02:54 2017 +0200
@@ -38,7 +38,7 @@
 adhoc_overloading
   vars term_vars
 
-value "vars (Fun ''f'' [Var 0, Var 1])"
+value [nbe] "vars (Fun ''f'' [Var 0, Var 1])"
 
 fun rule_vars :: "('a, 'b) term \<times> ('a, 'b) term \<Rightarrow> 'b set" where
   "rule_vars (l, r) = vars l \<union> vars r"
@@ -46,7 +46,7 @@
 adhoc_overloading
   vars rule_vars
 
-value "vars (Var 1, Var 0)"
+value [nbe] "vars (Var 1, Var 0)"
 
 definition trs_vars :: "(('a, 'b) term \<times> ('a, 'b) term) set \<Rightarrow> 'b set" where
   "trs_vars R = \<Union>(rule_vars ` R)"
@@ -54,7 +54,7 @@
 adhoc_overloading
   vars trs_vars
 
-value "vars {(Var 1, Var 0)}"
+value [nbe] "vars {(Var 1, Var 0)}"
 
 text \<open>Sometimes it is necessary to add explicit type constraints
 before a variant can be determined.\<close>
diff -r 455ca98d9de3 -r 882abe912da9 src/HOL/ex/Normalization_by_Evaluation.thy
--- a/src/HOL/ex/Normalization_by_Evaluation.thy	Sat Aug 05 22:12:41 2017 +0200
+++ b/src/HOL/ex/Normalization_by_Evaluation.thy	Sun Aug 06 15:02:54 2017 +0200
@@ -68,20 +68,20 @@
 lemma "map (%f. f True) ([id, g, Not] @ fs) = [True, g True, False] @ map (%f. f True) fs"
   by normalization rule
 lemma "rev [a, b, c] = [c, b, a]" by normalization
-value "rev (a#b#cs) = rev cs @ [b, a]"
-value "map (%F. F [a,b,c::'x]) (map map [f,g,h])"
-value "map (%F. F ([a,b,c] @ ds)) (map map ([f,g,h]@fs))"
-value "map (%F. F [Z,S Z,S(S Z)]) (map map [S,add (S Z),mul (S(S Z)),id])"
+value [nbe] "rev (a#b#cs) = rev cs @ [b, a]"
+value [nbe] "map (%F. F [a,b,c::'x]) (map map [f,g,h])"
+value [nbe] "map (%F. F ([a,b,c] @ ds)) (map map ([f,g,h]@fs))"
+value [nbe] "map (%F. F [Z,S Z,S(S Z)]) (map map [S,add (S Z),mul (S(S Z)),id])"
 lemma "map (%x. case x of None \<Rightarrow> False | Some y \<Rightarrow> True) [None, Some ()] = [False, True]" 
   by normalization
-value "case xs of [] \<Rightarrow> True | x#xs \<Rightarrow> False"
-value "map (%x. case x of None \<Rightarrow> False | Some y \<Rightarrow> True) xs = P"
+value [nbe] "case xs of [] \<Rightarrow> True | x#xs \<Rightarrow> False"
+value [nbe] "map (%x. case x of None \<Rightarrow> False | Some y \<Rightarrow> True) xs = P"
 lemma "let x = y in [x, x] = [y, y]" by normalization
 lemma "Let y (%x. [x,x]) = [y, y]" by normalization
-value "case n of Z \<Rightarrow> True | S x \<Rightarrow> False"
+value [nbe] "case n of Z \<Rightarrow> True | S x \<Rightarrow> False"
 lemma "(%(x,y). add x y) (S z,S z) = S (add z (S z))" by normalization
-value "filter (%x. x) ([True,False,x]@xs)"
-value "filter Not ([True,False,x]@xs)"
+value [nbe] "filter (%x. x) ([True,False,x]@xs)"
+value [nbe] "filter Not ([True,False,x]@xs)"
 
 lemma "[x,y,z] @ [a,b,c] = [x, y, z, a, b, c]" by normalization
 lemma "(%(xs, ys). xs @ ys) ([a, b, c], [d, e, f]) = [a, b, c, d, e, f]" by normalization
@@ -106,7 +106,7 @@
 lemma "[Suc 0, 0] = [Suc 0, 0]" by normalization
 lemma "max (Suc 0) 0 = Suc 0" by normalization
 lemma "(42::rat) / 1704 = 1 / 284 + 3 / 142" by normalization
-value "Suc 0 \<in> set ms"
+value [nbe] "Suc 0 \<in> set ms"
 
 (* non-left-linear patterns, equality by extensionality *)
 
@@ -115,13 +115,13 @@
 lemma "(f o g) x = f (g x)" by normalization
 lemma "(f o id) x = f x" by normalization
 lemma "(id :: bool \<Rightarrow> bool) = id" by normalization
-value "(\<lambda>x. x)"
+value [nbe] "(\<lambda>x. x)"
 
 (* Church numerals: *)
 
-value "(%m n f x. m f (n f x)) (%f x. f(f(f(x)))) (%f x. f(f(f(x))))"
-value "(%m n f x. m (n f) x) (%f x. f(f(f(x)))) (%f x. f(f(f(x))))"
-value "(%m n. n m) (%f x. f(f(f(x)))) (%f x. f(f(f(x))))"
+value [nbe] "(%m n f x. m f (n f x)) (%f x. f(f(f(x)))) (%f x. f(f(f(x))))"
+value [nbe] "(%m n f x. m (n f) x) (%f x. f(f(f(x)))) (%f x. f(f(f(x))))"
+value [nbe] "(%m n. n m) (%f x. f(f(f(x)))) (%f x. f(f(f(x))))"
 
 (* handling of type classes in connection with equality *)
 
diff -r 455ca98d9de3 -r 882abe912da9 src/HOL/ex/Transitive_Closure_Table_Ex.thy
--- a/src/HOL/ex/Transitive_Closure_Table_Ex.thy	Sat Aug 05 22:12:41 2017 +0200
+++ b/src/HOL/ex/Transitive_Closure_Table_Ex.thy	Sun Aug 06 15:02:54 2017 +0200
@@ -24,7 +24,7 @@
 values "{x. test\<^sup>*\<^sup>* A x}"
 values "{x. test\<^sup>*\<^sup>* x C}"
 
-value "test\<^sup>*\<^sup>* A C"
-value "test\<^sup>*\<^sup>* C A"
+value [nbe] "test\<^sup>*\<^sup>* A C"
+value [nbe] "test\<^sup>*\<^sup>* C A"
 
 end