feat(frontends/lean/pp): add option to hide binder types

src/frontends/lean/pp.cpp

@@ -292,6 +292,7 @@ void pretty_fn::set_options_core(options const & _o) {
     m_numerals        = get_pp_numerals(o);
     m_abbreviations   = get_pp_abbreviations(o);
     m_preterm         = get_pp_preterm(o);
+    m_binder_types    = get_pp_binder_types(o);
     m_hide_full_terms = get_formatter_hide_full_terms(o);
     m_num_nat_coe     = m_numerals && !m_coercion;
 }
@@ -669,8 +670,10 @@ format pretty_fn::pp_binder(expr const & local) {
     if (bi != binder_info())
         r += format(open_binder_string(bi, m_unicode));
     r += format(local_pp_name(local));
+    if (m_binder_types) {
         r += space();
         r += compose(colon(), nest(m_indent, compose(line(), pp_child(mlocal_type(local), 0).fmt())));
+    }
     if (bi != binder_info())
         r += format(close_binder_string(bi, m_unicode));
     return r;
@@ -678,12 +681,16 @@ format pretty_fn::pp_binder(expr const & local) {
 
 format pretty_fn::pp_binder_block(buffer<name> const & names, expr const & type, binder_info const & bi) {
     format r;
+    if (m_binder_types || bi != binder_info())
         r += format(open_binder_string(bi, m_unicode));
     for (name const & n : names) {
         r += format(n);
-        r += space();
     }
+    if (m_binder_types) {
+        r += space();
         r += compose(colon(), nest(m_indent, compose(line(), pp_child(type, 0).fmt())));
+    }
+    if (m_binder_types || bi != binder_info())
         r += format(close_binder_string(bi, m_unicode));
     return group(r);
 }

src/frontends/lean/pp.h

@@ -70,6 +70,7 @@ private:
     bool                    m_abbreviations;
     bool                    m_hide_full_terms;
     bool                    m_preterm;
+    bool                    m_binder_types;
 
     name mk_metavar_name(name const & m);
     name mk_local_name(name const & n, name const & suggested);

src/frontends/lean/print_cmd.cpp

@@ -387,7 +387,7 @@ static bool print_constant(parser const & p, char const * kind, declaration cons
         out << "protected ";
     out << kind << " " << to_user_name(p.env(), d.get_name());
     print_attributes(p, d.get_name());
-    out << " : " << d.get_type();
+    out.update_options(out.get_options().update((name {"pp", "binder_types"}), true)) << " : " << d.get_type();
     if (is_def)
         out << " :=";
     out << "\n";

src/library/pp_options.cpp

@@ -75,6 +75,10 @@ Author: Leonardo de Moura
 #define LEAN_DEFAULT_PP_GOAL_MAX_HYPS 200
 #endif
 
+#ifndef LEAN_DEFAULT_PP_BINDER_TYPES
+#define LEAN_DEFAULT_PP_BINDER_TYPES false
+#endif
+
 #ifndef LEAN_DEFAULT_PP_ALL
 #define LEAN_DEFAULT_PP_ALL false
 #endif
@@ -97,6 +101,7 @@ static name * g_pp_abbreviations   = nullptr;
 static name * g_pp_preterm         = nullptr;
 static name * g_pp_goal_compact    = nullptr;
 static name * g_pp_goal_max_hyps   = nullptr;
+static name * g_pp_binder_types    = nullptr;
 static name * g_pp_all             = nullptr;
 static list<options> * g_distinguishing_pp_options = nullptr;
 
@@ -119,6 +124,7 @@ void initialize_pp_options() {
     g_pp_all             = new name{"pp", "all"};
     g_pp_goal_compact    = new name{"pp", "goal", "compact"};
     g_pp_goal_max_hyps   = new name{"pp", "goal", "max_hypotheses"};
+    g_pp_binder_types    = new name{"pp", "binder_types"};
 
     register_unsigned_option(*g_pp_max_depth, LEAN_DEFAULT_PP_MAX_DEPTH,
                              "(pretty printer) maximum expression depth, after that it will use ellipsis");
@@ -156,6 +162,8 @@ void initialize_pp_options() {
                          "(pretty printer) try to display goal in a single line when possible");
     register_unsigned_option(*g_pp_goal_max_hyps, LEAN_DEFAULT_PP_GOAL_MAX_HYPS,
                              "(pretty printer) maximum number of hypotheses to be displayed");
+    register_bool_option(*g_pp_binder_types, LEAN_DEFAULT_PP_BINDER_TYPES,
+                         "(pretty printer) display types of lambda and Pi parameters");
     register_bool_option(*g_pp_all, LEAN_DEFAULT_PP_ALL,
                          "(pretty printer) display coercions, implicit parameters, fully qualified names, universes, "
                          "and disable abbreviations, beta reduction and notation during pretty printing");
@@ -223,6 +231,7 @@ bool     get_pp_abbreviations(options const & opts)   { return opts.get_bool(*g_
 bool     get_pp_preterm(options const & opts)         { return opts.get_bool(*g_pp_preterm, LEAN_DEFAULT_PP_PRETERM); }
 bool     get_pp_goal_compact(options const & opts)    { return opts.get_bool(*g_pp_goal_compact, LEAN_DEFAULT_PP_GOAL_COMPACT); }
 unsigned get_pp_goal_max_hyps(options const & opts)   { return opts.get_unsigned(*g_pp_goal_max_hyps, LEAN_DEFAULT_PP_GOAL_MAX_HYPS); }
+bool     get_pp_binder_types(options const & opts)    { return opts.get_bool(*g_pp_binder_types, LEAN_DEFAULT_PP_BINDER_TYPES); }
 bool     get_pp_all(options const & opts)             { return opts.get_bool(*g_pp_all, LEAN_DEFAULT_PP_ALL); }
 
 list<options> const & get_distinguishing_pp_options() { return *g_distinguishing_pp_options; }

src/library/pp_options.h

@@ -37,6 +37,7 @@ bool     get_pp_abbreviations(options const & opts);
 bool     get_pp_preterm(options const & opts);
 bool     get_pp_goal_compact(options const & opts);
 unsigned get_pp_goal_max_hyps(options const & opts);
+bool     get_pp_binder_types(options const & opts);
 bool     get_pp_all(options const & opts);
 list<options> const & get_distinguishing_pp_options();
 

tests/lean/pp_binder_types.lean

@@ -0,0 +1,7 @@
+open nat
+
+definition f (n : nat) (H : n = n) := λm, id (n + m)
+print f
+
+set_option pp.binder_types true
+print f

tests/lean/pp_binder_types.lean.expected.out

@@ -0,0 +1,4 @@
+definition f : Π (n : ℕ), n = n → ℕ → ℕ :=
+λ n H m, id (n + m)
+definition f : Π (n : ℕ), n = n → ℕ → ℕ :=
+λ (n : ℕ) (H : n = n) (m : ℕ), id (n + m)