Adding upstream version 1.44.3.upstream/1.44.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 146 insertions, 0 deletions

diff --git a/ml/dlib/examples/config_reader_ex.cpp b/ml/dlib/examples/config_reader_ex.cpp
new file mode 100644
index 00000000..02ad1cc6
--- /dev/null
+++ b/ml/dlib/examples/config_reader_ex.cpp
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+// The contents of this file are in the public domain. See LICENSE_FOR_EXAMPLE_PROGRAMS.txt
+/*
+
+    This is an example illustrating the use of the config_reader component  
+    from the dlib C++ Library.
+
+    This example uses the config_reader to load a config file and then
+    prints out the values of various fields in the file.
+*/
+
+
+#include <dlib/config_reader.h>
+#include <iostream>
+#include <fstream>
+#include <vector>
+
+
+using namespace std;
+using namespace dlib;
+
+// ----------------------------------------------------------------------------------------
+// For reference, the contents of the config file used in this example is reproduced below:  
+/*
+
+# This is an example config file.  Note that # is used to create a comment.
+
+# At its most basic level a config file is just a bunch of key/value pairs.
+# So for example:
+key1 = value2
+dlib = a C++ library
+
+# You can also define "sub blocks" in your config files like so
+user1 
+{ 
+    # Inside a sub block you can list more key/value pairs.  
+    id = 42
+    name = davis
+
+    # you can also nest sub-blocks as deep as you want
+    details 
+    { 
+        editor = vim
+        home_dir = /home/davis
+    }
+}
+user2 { 
+    id = 1234
+    name = joe
+    details { 
+        editor = emacs
+        home_dir = /home/joe
+    }
+}
+
+*/
+// ----------------------------------------------------------------------------------------
+
+void print_config_reader_contents (
+    const config_reader& cr,
+    int depth = 0
+);
+/*
+    This is a simple function that recursively walks through everything in 
+    a config reader and prints it to the screen.
+*/
+
+// ----------------------------------------------------------------------------------------
+
+int main()
+{
+    try
+    {
+        config_reader cr("config.txt");
+
+        // Use our recursive function to print everything in the config file.
+        print_config_reader_contents(cr);
+
+        // Now let's access some of the fields of the config file directly.  You 
+        // use [] for accessing key values and .block() for accessing sub-blocks.
+
+        // Print out the string value assigned to key1 in the config file
+        cout << cr["key1"] << endl;
+
+        // Print out the name field inside the user1 sub-block
+        cout << cr.block("user1")["name"] << endl;
+        // Now print out the editor field in the details block
+        cout << cr.block("user1").block("details")["editor"] << endl;
+
+        
+        // Note that you can use get_option() to easily convert fields into 
+        // non-string types.  For example, the config file has an integer id 
+        // field that can be converted into an int like so:
+        int id1 = get_option(cr,"user1.id",0); 
+        int id2 = get_option(cr,"user2.id",0); 
+        cout << "user1's id is " << id1 << endl;
+        cout << "user2's id is " << id2 << endl;
+        // The third argument to get_option() is the default value returned if 
+        // the config reader doesn't contain a corresponding entry.  So for 
+        // example, the following prints 321 since there is no user3.
+        int id3 = get_option(cr,"user3.id",321); 
+        cout << "user3's id is " << id3 << endl;
+
+    }
+    catch (exception& e)
+    {
+        // Finally, note that the config_reader throws exceptions if the config
+        // file is corrupted or if you ask it for a key or block that doesn't exist. 
+        // Here we print out any such error messages.
+        cout << e.what() << endl;
+    }
+}
+
+// ----------------------------------------------------------------------------------------
+
+void print_config_reader_contents (
+    const config_reader& cr,
+    int depth 
+)
+{
+    // Make a string with depth*4 spaces in it.  
+    const string padding(depth*4, ' ');
+
+    // We can obtain a list of all the keys and sub-blocks defined
+    // at the current level in the config reader like so:
+    vector<string> keys, blocks;
+    cr.get_keys(keys);
+    cr.get_blocks(blocks);
+
+    // Now print all the key/value pairs
+    for (unsigned long i = 0; i < keys.size(); ++i)
+        cout << padding << keys[i] << " = " << cr[keys[i]] << endl;
+
+    // Now print all the sub-blocks. 
+    for (unsigned long i = 0; i < blocks.size(); ++i)
+    {
+        // First print the block name
+        cout << padding << blocks[i] << " { " << endl;
+        // Now recursively print the contents of the sub block.  Note that the cr.block()
+        // function returns another config_reader that represents the sub-block.  
+        print_config_reader_contents(cr.block(blocks[i]), depth+1);
+        cout << padding << "}" << endl;
+    }
+}
+
+// ----------------------------------------------------------------------------------------
+