title: How can I install package simmer in R ?(on Mac OS X)
body: <p>OS version : macOS Catalina 10.15.4</p>
  
  <p>I tried to install simmer package but I got error massages from r studio.</p>
  
  <p>'''</p>
  
  <pre><code>&gt; devtools::install_github("r-simmer/simmer")
  Downloading GitHub repo r-simmer/simmer@master
  ✔  checking for file ‘/private/var/folders/pz/35d87wwn2_19t3h08hkv42m00000gn/T/RtmpaX72mc/remotes196b67508c78/r-simmer-simmer-e10a7dc/DESCRIPTION’ ...
  ─  preparing ‘simmer’:
  ✔  checking DESCRIPTION meta-information ...
  ─  cleaning src
  ─  installing the package to process help pages
           -----------------------------------
  ─  installing *source* package ‘simmer’ ...
     ** using staged installation
     ** libs
     clang++ -std=gnu++11 -I"/Library/Frameworks/R.framework/Resources/include" -DNDEBUG -I../inst/include -DBOOST_NO_LONG_LONG -DBOOST_NO_AUTO_PTR -DRCPP_USE_UNWIND_PROTECT -I"/Library/Frameworks/R.framework/Versions/3.6/Resources/library/Rcpp/include" -I"/Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include" -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk -I/usr/local/include  -fPIC  -Wall -g -O2  -c RcppExports.cpp -o RcppExports.o
     In file included from RcppExports.cpp:4:
     In file included from ./../inst/include/simmer.h:21:
     In file included from ../inst/include/simmer/common.h:32:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/container/set.hpp:15:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config.hpp:57:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config/platform/macos.hpp:28:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config/detail/posix_features.hpp:18:
     In file included from /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/unistd.h:655:
     /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/gethostuuid.h:39:17: error: C++ requires a type specifier for all declarations
     int gethostuuid(uuid_t, const struct timespec *) __OSX_AVAILABLE_STARTING(__MAC_10_5, __IPHONE_NA);
                     ^
     In file included from RcppExports.cpp:4:
     In file included from ./../inst/include/simmer.h:21:
     In file included from ../inst/include/simmer/common.h:32:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/container/set.hpp:15:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config.hpp:57:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config/platform/macos.hpp:28:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config/detail/posix_features.hpp:18:
     /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/unistd.h:662:27: error: unknown type name 'uuid_t'; did you mean 'uid_t'?
     int      getsgroups_np(int *, uuid_t);
                                   ^
     /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/_types/_uid_t.h:31:31: note: 'uid_t' declared here
     typedef __darwin_uid_t        uid_t;
                                   ^
     In file included from RcppExports.cpp:4:
     In file included from ./../inst/include/simmer.h:21:
     In file included from ../inst/include/simmer/common.h:32:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/container/set.hpp:15:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config.hpp:57:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config/platform/macos.hpp:28:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config/detail/posix_features.hpp:18:
     /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/unistd.h:664:27: error: unknown type name 'uuid_t'; did you mean 'uid_t'?
     int      getwgroups_np(int *, uuid_t);
                                   ^
     /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/_types/_uid_t.h:31:31: note: 'uid_t' declared here
     typedef __darwin_uid_t        uid_t;
                                   ^
     In file included from RcppExports.cpp:4:
     In file included from ./../inst/include/simmer.h:21:
     In file included from ../inst/include/simmer/common.h:32:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/container/set.hpp:15:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config.hpp:57:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config/platform/macos.hpp:28:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config/detail/posix_features.hpp:18:
     /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/unistd.h:727:31: error: unknown type name 'uuid_t'; did you mean 'uid_t'?
     int      setsgroups_np(int, const uuid_t);
                                       ^
     /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/_types/_uid_t.h:31:31: note: 'uid_t' declared here
     typedef __darwin_uid_t        uid_t;
                                   ^
     In file included from RcppExports.cpp:4:
     In file included from ./../inst/include/simmer.h:21:
     In file included from ../inst/include/simmer/common.h:32:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/container/set.hpp:15:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config.hpp:57:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config/platform/macos.hpp:28:
     In file included from /Library/Frameworks/R.framework/Versions/3.6/Resources/library/BH/include/boost/config/detail/posix_features.hpp:18:
     /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/unistd.h:729:31: error: unknown type name 'uuid_t'; did you mean 'uid_t'?
     int      setwgroups_np(int, const uuid_t);
                                       ^
     /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/_types/_uid_t.h:31:31: note: 'uid_t' declared here
     typedef __darwin_uid_t        uid_t;
                                   ^
     5 errors generated.
     make: *** [RcppExports.o] Error 1
     ERROR: compilation failed for package ‘simmer’
  ─  removing ‘/private/var/folders/pz/35d87wwn2_19t3h08hkv42m00000gn/T/Rtmp5agreT/Rinst19c0507f76cd/simmer’
           -----------------------------------
     ERROR: package installation failed
  Error: Failed to install 'simmer' from GitHub:
    System command error, exit status: 1, stdout + stderr (last 10 lines):
  E&gt;                                   ^
  E&gt; /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/_types/_uid_t.h:31:31: note: 'uid_t' declared here
  E&gt; typedef __darwin_uid_t        uid_t;
  E&gt;                               ^
  E&gt; 5 errors generated.
  E&gt; make: *** [RcppExports.o] Error 1
  E&gt; ERROR: compilation failed for package ‘simmer’
  E&gt; * removing ‘/private/var/folders/pz/35d87wwn2_19t3h08hkv42m00000gn/T/Rtmp5agreT/Rinst19c0507f76cd/simmer’
  E&gt;       -----------------------------------
  E&gt; ERROR: package installation failed
  </code></pre>
  
  <p>'''</p>
  
  <p>I found some informations from google. They said this problem is occured because of macOS but I can't find any solutions. Is there any other route to install the package?
  or How can I solve this problem? </p>