r: convert to disambiguation page; r.zsh: add alias page (#21036)

Co-authored-by: Ivan Baluta <ivanbaluta.dev@gmail.com>

pages/common/r.1.md

@@ -0,0 +1,32 @@
+# R
+
+> R language interpreter.
+> More information: <https://manned.org/R>.
+
+- Start a REPL (interactive shell):
+
+`R`
+
+- Start R in vanilla mode (i.e. a blank session that doesn't save the workspace at the end):
+
+`R --vanilla`
+
+- Execute a file:
+
+`R {{[-f|--file]}} {{path/to/file.R}}`
+
+- Execute an R expression and then exit:
+
+`R -e {{expr}}`
+
+- Run R with a debugger:
+
+`R {{[-d|--debugger]}} {{debugger}}`
+
+- Check R packages from package sources:
+
+`R CMD check {{path/to/package_source}}`
+
+- Display version:
+
+`R --version`

pages/common/r.md

@@ -1,32 +1,11 @@
-# R
+# r
 
-> R language interpreter.
-> More information: <https://manned.org/R>.
+> `r` can refer to multiple commands with the same name.
 
-- Start a REPL (interactive shell):
+- View documentation for the R language interpreter:
 
-`R`
+`tldr r.1`
 
-- Start R in vanilla mode (i.e. a blank session that doesn't save the workspace at the end):
+- View documentation for the Zsh command:
 
-`R --vanilla`
-
-- Execute a file:
-
-`R {{[-f|--file]}} {{path/to/file.R}}`
-
-- Execute an R expression and then exit:
-
-`R -e {{expr}}`
-
-- Run R with a debugger:
-
-`R {{[-d|--debugger]}} {{debugger}}`
-
-- Check R packages from package sources:
-
-`R CMD check {{path/to/package_source}}`
-
-- Display version:
-
-`R --version`
+`tldr r.zsh`

pages/common/r.zsh.md

@@ -0,0 +1,7 @@
+# r
+
+> This command is an alias of `fc -e -`.
+
+- View documentation for the original command:
+
+`tldr fc`