Updated C++ standard to C++17

C++17 should be universal enough by now.

This raises the minimum CMake to 3.8, which should also pose no problem since
Ubuntu 18.04 already shipped with CMake 3.10.

C++17's 'if' initialization statement is now used in an efficient
implementation of 'join' for vector<string>, found on StackOverflow.

2 files changed, 25 insertions, 7 deletions

diff --git a/src/utils/stringutils.cpp b/src/utils/stringutils.cpp
index 5083770c..57138005 100644
--- a/src/utils/stringutils.cpp
+++ b/src/utils/stringutils.cpp
@@ -85,7 +85,7 @@ const char *ipToString(int address)
 std::string strprintf(char const *format, ...)
 {
     char buf[256];
-    va_list(args);
+    va_list args;
     va_start(args, format);
     int nb = vsnprintf(buf, 256, format, args);
     va_end(args);
@@ -191,7 +191,7 @@ bool getBoolFromString(const std::string &text, bool def)
         return def;
 }
 
-std::string autocomplete(std::vector<std::string> &candidates,
+std::string autocomplete(const std::vector<std::string> &candidates,
                          std::string base)
 {
     auto i = candidates.begin();
@@ -232,7 +232,7 @@ std::string normalize(const std::string &name)
     return toLower(trim(normalized));
 }
 
-std::string removeTrailingSymbol(const std::string& s, const char c)
+std::string removeTrailingSymbol(const std::string &s, const char c)
 {
     // Remove the trailing symblol at the end of the string
     if (!s.empty() && s.at(s.size() - 1) == c)
@@ -240,7 +240,7 @@ std::string removeTrailingSymbol(const std::string& s, const char c)
     return std::string(s);
 }
 
-std::string getHostNameFromURL(const std::string& url)
+std::string getHostNameFromURL(const std::string &url)
 {
     std::string myHostName;
 
@@ -276,3 +276,15 @@ std::string getHostNameFromURL(const std::string& url)
 
     return myHostName;
 }
+
+std::string join(const std::vector<std::string> &strings, const char *separator)
+{
+    std::string result;
+    if (auto i = strings.begin(), e = strings.end(); i != e)
+    {
+        result += *i++;
+        for (; i != e; ++i)
+            result.append(separator).append(*i);
+    }
+    return result;
+}
diff --git a/src/utils/stringutils.h b/src/utils/stringutils.h
index b83bc580..cd80b60f 100644
--- a/src/utils/stringutils.h
+++ b/src/utils/stringutils.h
@@ -141,7 +141,7 @@ bool getBoolFromString(const std::string &text, bool def = false);
 /**
  * Returns the most approaching string of base from candidates.
  */
-std::string autocomplete(std::vector<std::string> &candidates,
+std::string autocomplete(const std::vector<std::string> &candidates,
                          std::string base);
 
 /**
@@ -152,12 +152,18 @@ std::string normalize(const std::string &name);
 /**
  * Remove a potential trailing symbol from a string.
  */
-std::string removeTrailingSymbol(const std::string& s, const char c);
+std::string removeTrailingSymbol(const std::string &s, const char c);
 
 /**
  * Gets the hostname out of the given URL.
  * i.e.: http://www.manasource.org:9601 -> www.manasource.org
  */
-std::string getHostNameFromURL(const std::string& url);
+std::string getHostNameFromURL(const std::string &url);
+
+/**
+ * Joins a vector of strings into one string, separated by the given
+ * separator.
+ */
+std::string join(const std::vector<std::string> &strings, const char *separator);
 
 #endif // UTILS_STRINGUTILS_H