title: How to install specific version of "rlang" package in R?
body: <p>I am using R studio on Mac OS and I want to use <code>caret</code> package for some data analysis. However, <code>caret</code> depends on <code>rlang</code> package and when I try to load <code>caret</code> package I get this error - </p>
  
  <pre><code>&gt; library(caret)
  Error: package or namespace load failed for ‘caret’ in loadNamespace(i, c(lib.loc, .libPaths()), versionCheck = vI[[i]]):
   namespace ‘rlang’ 0.2.2 is already loaded, but &gt;= 0.3.0.1 is required
  In addition: Warning message:
  package ‘caret’ was built under R version 3.4.4 
  </code></pre>
  
  <p>I removed the <code>rlang</code> package from the UI and tried installing it again but I am facing below issue -</p>
  
  <pre><code>&gt; install.packages("rlang")
  trying URL 'https://cran.rstudio.com/bin/macosx/el-capitan/contrib/3.4/rlang_0.3.0.1.tgz'
  Content type 'application/x-gzip' length 1074663 bytes (1.0 MB)
  ==================================================
  downloaded 1.0 MB
  
  
  The downloaded binary packages are in
      /var/folders/kh/9lkdq11x3sv56717v0700p_r_16f9p/T//RtmplrCvGX/downloaded_packages
  &gt; library(rlang)
  Error in value[[3L]](cond) : 
    Package ‘rlang’ version 0.2.2 cannot be unloaded:
   Error in unloadNamespace(package) : namespace ‘rlang’ is imported by ‘tidyr’, ‘purrr’, ‘ggplot2’, ‘plotly’, ‘dplyr’, ‘tibble’, ‘pillar’ so cannot be unloaded
  In addition: Warning message:
  package ‘rlang’ was built under R version 3.4.4 
  </code></pre>
  
  <p>Here is my <code>sessionInfo()</code></p>
  
  <pre><code>R version 3.4.3 (2017-11-30)
  Platform: x86_64-apple-darwin15.6.0 (64-bit)
  Running under: macOS  10.14
  
  Matrix products: default
  BLAS: /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib
  LAPACK: /Library/Frameworks/R.framework/Versions/3.4/Resources/lib/libRlapack.dylib
  
  locale:
  [1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8
  
  attached base packages:
  [1] stats     graphics  grDevices utils     datasets  methods   base     
  
  other attached packages:
  [1] dummies_1.5.6       ISLR_1.2            mltools_0.3.5       data.table_1.10.4-3 ggplot2_3.0.0.9000  lattice_0.20-35    
  
  loaded via a namespace (and not attached):
   [1] reshape2_1.4.3     purrr_0.2.4        colorspace_1.3-2   htmltools_0.3.6    viridisLite_0.3.0  yaml_2.1.16        plotly_4.8.0      
   [8] rlang_0.3.0.1      ModelMetrics_1.2.2 pillar_1.1.0       glue_1.2.0         withr_2.1.2        bindrcpp_0.2       foreach_1.4.4     
  [15] bindr_0.1          plyr_1.8.4         stringr_1.2.0      munsell_0.5.0      gtable_0.2.0       htmlwidgets_1.2    devtools_1.13.4   
  [22] codetools_0.2-15   memoise_1.1.0      curl_3.1           Rcpp_0.12.18       scales_1.0.0       jsonlite_1.5       digest_0.6.16     
  [29] stringi_1.1.6      dplyr_0.7.4        grid_3.4.3         tools_3.4.3        magrittr_1.5       lazyeval_0.2.1     tibble_1.4.2      
  [36] tidyr_0.7.2        pkgconfig_2.0.1    Matrix_1.2-12      assertthat_0.2.0   httr_1.3.1         iterators_1.0.10   R6_2.2.2          
  [43] nlme_3.1-131       compiler_3.4.3     git2r_0.21.0 
  </code></pre>