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sphinx_doc_src/cmds/if.rst

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+\section if if - conditionally execute a command
+
+\subsection if-synopsis Synopsis
+\fish{synopsis}
+if CONDITION; COMMANDS_TRUE...;
+[else if CONDITION2; COMMANDS_TRUE2...;]
+[else; COMMANDS_FALSE...;]
+end
+\endfish
+
+\subsection if-description Description
+
+`if` will execute the command `CONDITION`. If the condition's exit status is 0, the commands `COMMANDS_TRUE` will execute.  If the exit status is not 0 and `else` is given, `COMMANDS_FALSE` will be executed.
+
+You can use <a href="#and">`and`</a> or <a href="#or">`or`</a> in the condition. See the second example below.
+
+The exit status of the last foreground command to exit can always be accessed using the <a href="index.html#variables-status">$status</a> variable.
+
+\subsection if-example Example
+
+The following code will print `foo.txt exists` if the file foo.txt exists and is a regular file, otherwise it will print `bar.txt exists` if the file bar.txt exists and is a regular file, otherwise it will print `foo.txt and bar.txt do not exist`.
+
+\fish
+if test -f foo.txt
+    echo foo.txt exists
+else if test -f bar.txt
+    echo bar.txt exists
+else
+    echo foo.txt and bar.txt do not exist
+end
+\endfish
+
+The following code will print "foo.txt exists and is readable" if foo.txt is a regular file and readable
+\fish
+if test -f foo.txt
+   and test -r foo.txt
+   echo "foo.txt exists and is readable"
+end
+\endfish