[Boost-commit] svn:boost r69594 - in sandbox/local: . boost/local/aux_/function_macros/code_ libs/local/example

Subject: [Boost-commit] svn:boost r69594 - in sandbox/local: . boost/local/aux_/function_macros/code_ libs/local/example
From: lorcaminiti_at_[hidden]
Date: 2011-03-05 19:38:52

Author: lcaminiti
Date: 2011-03-05 19:38:44 EST (Sat, 05 Mar 2011)
New Revision: 69594
URL: http://svn.boost.org/trac/boost/changeset/69594

Log:
Added GCC nested function example (not all compiling).
Added D-style scope guards (exit, success, and failure) examples.
Added:
   sandbox/local/libs/local/example/gcc-access_va.cpp   (contents, props changed)
   sandbox/local/libs/local/example/gcc-goto.cpp   (contents, props changed)
   sandbox/local/libs/local/example/gcc-square.cpp   (contents, props changed)
   sandbox/local/libs/local/example/gcc-square_va.cpp   (contents, props changed)
   sandbox/local/libs/local/example/gcc-store.cpp   (contents, props changed)
   sandbox/local/libs/local/example/scope_guards_errno.cpp   (contents, props changed)
   sandbox/local/libs/local/example/scope_guards_except.cpp   (contents, props changed)
   sandbox/local/libs/local/example/scope_guards_se.cpp   (contents, props changed)
Text files modified: 
   sandbox/local/TODO.txt                                           |     6 ++++++                                  
   sandbox/local/boost/local/aux_/function_macros/code_/functor.hpp |     3 +++                                     
   2 files changed, 9 insertions(+), 0 deletions(-)

Modified: sandbox/local/TODO.txt
==============================================================================
--- sandbox/local/TODO.txt	(original)
+++ sandbox/local/TODO.txt	2011-03-05 19:38:44 EST (Sat, 05 Mar 2011)
@@ -10,9 +10,15 @@
 
 * Docs: If `, default ...` syntax seems strange for C99, programmers can always use `#define WITH_DEFAULT(x) , default x` or similar macro instead.
 
+* Docs: Add D-Stype Scope Guards examples to docs.
+
 
 * Code: Try seriously to make nested locals to work...
 
+* Code: Add `BOOST_LOCAL_CONFIG_COMPLIANT` macro (#undef by default) that forces 100% C++ standard compliant if #defined -- no variadic and no empy macro params. Similar to Boost.Typeof COMPLIANT -- but programmers must also #define Boost.Typeof COMPLIANT separately if they wish to do so.
+
+* Code: Make the member variable with the local function name used for recursion const so body cannot change it -- or better, make the body funciton const so it cannot change anything about the object (if possible)...
+
 * Code: Optimize macro expansion code for C++0x, C++03, etc. From John Bytheway:
 > Yes, in C++0x local structs can be passed as template parameters.
 > Obviously, in C++0x there are lambdas too, so you might think your

Modified: sandbox/local/boost/local/aux_/function_macros/code_/functor.hpp
==============================================================================
--- sandbox/local/boost/local/aux_/function_macros/code_/functor.hpp	(original)
+++ sandbox/local/boost/local/aux_/function_macros/code_/functor.hpp	2011-03-05 19:38:44 EST (Sat, 05 Mar 2011)
@@ -281,6 +281,9 @@
                         BOOST_LOCAL_AUX_FUNCTION_CODE_PARAM_UNBIND_DECL_WITH_DEFAULT, \
                         ~, unbinds) \
             ) /* end body function params */ \
+            /* const member func so it cannot change obj (reassign member */ \
+            /* var with local function name, etc) */ \
+            const \
             /* user local function definition `{ ... }` will follow here */ \
     /* `NAME` macro will close function class decl `};` here */ 
 

Added: sandbox/local/libs/local/example/gcc-access_va.cpp
==============================================================================
--- (empty file)
+++ sandbox/local/libs/local/example/gcc-access_va.cpp	2011-03-05 19:38:44 EST (Sat, 05 Mar 2011)
@@ -0,0 +1,14 @@
+
+#include <boost/local/function.hpp>
+
+void bar(int* array, int offset, int size) {
+    int BOOST_LOCAL_FUNCTION_PARAMS(int* array, int index, const bind offset) {
+        return array[index + offset];
+    }
+
+    for (int i = 0; i < size; ++i) {
+        std::cout << access(array, i) << std::endl;
+    }
+}
+
+

Added: sandbox/local/libs/local/example/gcc-goto.cpp
==============================================================================
--- (empty file)
+++ sandbox/local/libs/local/example/gcc-goto.cpp	2011-03-05 19:38:44 EST (Sat, 05 Mar 2011)
@@ -0,0 +1,26 @@
+
+#include <boost/local/function.hpp>
+#include <iostream>
+
+int print(int* array, int offset, int size) {
+    int BOOST_LOCAL_FUNCTION_PARAMS( (int* array) (int index)
+            (const bind offset) (const bind size) ) {
+        if (index > size) goto failure;
+        return array[index + offset];
+    } BOOST_LOCAL_FUNCTION_NAME(access)
+
+    for (int i = 0; i < size; ++i) {
+        std::cout << access(array, i) << std::endl;
+    }
+    return 0;
+
+failure:
+    return -1;
+}
+
+int main() {
+    int a[] = {1, 2, 3, 4, 5};
+    print(a, 1, 2);
+    return 0;
+}
+

Added: sandbox/local/libs/local/example/gcc-square.cpp
==============================================================================
--- (empty file)
+++ sandbox/local/libs/local/example/gcc-square.cpp	2011-03-05 19:38:44 EST (Sat, 05 Mar 2011)
@@ -0,0 +1,13 @@
+
+#include <boost/local/function.hpp>
+
+void add_square(double a, double b) {
+    double BOOST_LOCAL_FUNCTION(double z) {
+        return z * z;
+    } BOOST_LOCAL_FUNCTION_NAME(suare)
+
+    return square(a) + square(b);
+}
+
+
+

Added: sandbox/local/libs/local/example/gcc-square_va.cpp
==============================================================================
--- (empty file)
+++ sandbox/local/libs/local/example/gcc-square_va.cpp	2011-03-05 19:38:44 EST (Sat, 05 Mar 2011)
@@ -0,0 +1,13 @@
+
+#include <boost/local/function.hpp>
+
+void add_square(double a, double b) {
+    double BOOST_LOCAL_FUNCTION(double z) {
+        return z * z;
+    } BOOST_LOCAL_FUNCTION_NAME(suare)
+
+    return square(a) + square(b);
+}
+
+
+

Added: sandbox/local/libs/local/example/gcc-store.cpp
==============================================================================
--- (empty file)
+++ sandbox/local/libs/local/example/gcc-store.cpp	2011-03-05 19:38:44 EST (Sat, 05 Mar 2011)
@@ -0,0 +1,14 @@
+
+void intermediate(void (*store_func)(int, int), int size) {
+    store_func(size - 1, -1);
+}
+
+void hack(int* array, int size) {
+    void BOOST_LOCAL_FUNCTION_PARAMS(int index, int value, bind array) {
+        array[index] = value;
+    } BOOST_LOCAL_FUNCTION_NAME(store)
+
+    intermediate(store, size);
+}
+
+

Added: sandbox/local/libs/local/example/scope_guards_errno.cpp
==============================================================================
--- (empty file)
+++ sandbox/local/libs/local/example/scope_guards_errno.cpp	2011-03-05 19:38:44 EST (Sat, 05 Mar 2011)
@@ -0,0 +1,30 @@
+
+#include <boost/local/exit.hpp>
+#include <iostream>
+
+int f() {
+    int error = 0; // No error to start with.
+
+    BOOST_LOCAL_EXIT( (void) ) { // Same as D's `scope(exit)`.
+        std::cout << "exit" << std::endl;
+    } BOOST_LOCAL_EXIT_END
+
+    BOOST_LOCAL_EXIT( (const bind& error) ) { // Sane as D's `scope(success)`.
+        if (!error) std::cout << "success" << std::endl;
+    } BOOST_LOCAL_EXIT_END
+    
+    BOOST_LOCAL_EXIT( (const bind& error) ) { // Same as D's `scope(failure)`.
+        if (error) std::cout << "failure" << std::endl;
+    } BOOST_LOCAL_EXIT_END
+    
+    // Cannot use `return <NUMBER>` otherwise scope exits do not know the
+    // error number. Set error and exit using `return error` instead.
+    error = -2; return error;
+    error = -1; return error;
+}
+
+int main() {
+    std::cout << "error number: " << f() << std::endl;
+    return 0;
+}
+

Added: sandbox/local/libs/local/example/scope_guards_except.cpp
==============================================================================
--- (empty file)
+++ sandbox/local/libs/local/example/scope_guards_except.cpp	2011-03-05 19:38:44 EST (Sat, 05 Mar 2011)
@@ -0,0 +1,74 @@
+
+#include <boost/local/exit.hpp>
+#include <iostream>
+#include <stdexcept>
+
+struct exception_error_interface {
+    virtual operator bool() const = 0;
+    virtual void throw_if() const = 0;
+};
+
+template<typename E>
+struct exception_error: exception_error_interface {
+    template<typename A0>
+    explicit exception_error(A0 arg0): ex_(E(arg0)) {}
+    template<typename A0, typename A1>
+    exception_error(A0 arg0, A1 arg1): ex_(E(arg0, arg1)) {}
+    // Add more constructors for more parameters if needed...
+
+    operator bool() const { return true; }
+    void throw_if() const { throw ex_; }
+
+private:
+    E ex_; // I need the exception type `E` here so I can throw it later.
+};
+
+template<>
+struct exception_error<void> { // Use `void` for no error (cannot throw void).
+    exception_error(): err_() {} // No error by default.
+
+    template<typename E> // Construct with some error.
+    /* implicit */ exception_error(exception_error<E> const& err): err_(&err) {}
+    template<typename E> // Set some error.
+    exception_error& operator=(exception_error<E> const& err)
+        { err_ = &err; return *this; }
+
+    operator bool() const { return err_ && bool(*err_); }
+    // Select proper type to throw via polymorphism.
+    void throw_if() const { if (err_) err_->throw_if(); }
+
+private:
+    exception_error_interface const* err_;
+};
+
+void f() {
+    exception_error<void> error; // No error (i.e., `void`) to start with.
+    // This scope exit is special -- it's used to throw on exit if error.
+    BOOST_LOCAL_EXIT( (const bind& error) ) {
+        std::cout << "throwing if error" << std::endl;
+        error.throw_if(); // Throws if error set not to `exception_error<void>`.
+    } BOOST_LOCAL_EXIT_END
+
+    BOOST_LOCAL_EXIT( (void) ) { // Smae as D's `scope(exit)`.
+        std::cout << "exit" << std::endl;
+    } BOOST_LOCAL_EXIT_END
+
+    BOOST_LOCAL_EXIT( (const bind& error) ) { // Same as D's `scope(success)`.
+        if (!error) std::cout << "success" << std::endl;
+    } BOOST_LOCAL_EXIT_END
+    
+    BOOST_LOCAL_EXIT( (const bind& error) ) { // Same as D's `scope(failure)`.
+        if (error) std::cout << "failure" << std::endl;
+    } BOOST_LOCAL_EXIT_END
+    
+    // Cannot use `throw` otherwise scope exits are not executed. Set error
+    // and exit using `return` instead (the 1st scope exit will throw).
+    error = exception_error<std::runtime_error>("some error"); return;
+    error = exception_error<int>(-1); return;
+}
+
+int main() {
+    f();
+    return 0;
+}
+

Added: sandbox/local/libs/local/example/scope_guards_se.cpp
==============================================================================
--- (empty file)
+++ sandbox/local/libs/local/example/scope_guards_se.cpp	2011-03-05 19:38:44 EST (Sat, 05 Mar 2011)
@@ -0,0 +1,20 @@
+
+#include <boost/scope_exit.hpp>
+#include <iostream>
+#include <stdexcept>
+
+void f() {
+    bool error = false;
+
+    BOOST_SCOPE_EXIT( (&error) ) {
+        std::cout << "returning" << std::endl; // Not executed on throw.
+    } BOOST_SCOPE_EXIT_END
+
+    throw std::runtime_error("some error");
+}
+
+int main() {
+    f();
+    return 0;
+}
+