From b0991484624c0ddd4bdd45eb64619144f189b42a Mon Sep 17 00:00:00 2001 From: johannst Date: Sat, 18 Nov 2023 11:39:35 +0000 Subject: deploy: 947ca7041270c1a0bf8ac39387e611931f606aa1 --- print.html | 142 ++++++++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 112 insertions(+), 30 deletions(-) (limited to 'print.html') diff --git a/print.html b/print.html index ebd80f0..640587d 100644 --- a/print.html +++ b/print.html @@ -720,10 +720,16 @@ shell restart -x export to ENV -u unexport from ENV +

Special Variables ref

+
$status      # exit code of last command
+$pipestatus  # list of exit codes of pipe chain
+
+$CMD_DURATION   # runtime of last command in ms
+

Lists

In fish all variables are lists (start with index 1, but lists can't contain lists.

-
set foo a b c d
+
set foo a b c d
 
 echo $foo[1]      # a
 echo $foo[-1]     # d
@@ -731,40 +737,39 @@ echo $foo[2..3]   # b c
 echo $foo[1 3]    # a c
 

 
$ can be seen as dereference operator.

-
set foo a; set a 1337
+
set foo a; set a 1337
 echo $$foo  # outputs 1337
 

 
Cartesian product.

-
echo file.{h,cc}
+
echo file.{h,cc}
 # file.h file.cc
 
 echo {a,b}{1,2}
 # a1 b1 a2 b2
 

-
Special Variables (Lists)

-
$status      # exit code of last command
-$pipestatus  # list of exit codes of pipe chain
-
-$CMD_DURATION   # runtime of last command in ms
-

-
*PATH

+
*PATH ref

 
Lists ending with PATH are automatically split at : when used and joined
-with : when exported to the environment.

-
set -x BLA_PATH a:b:c:d
-echo $BLA_PATH              # a b c d
-env | grep BLA_PATH         # BLA_PATH=a:b:c:d
+with : when quoted or exported to the environment.

+
set -x BLA_PATH a:b:c:d
+echo $BLA_PATH           # a b c d
+echo "$BLA_PATH"         # a:b:c:d          (quoted)
+env | grep BLA_PATH      # BLA_PATH=a:b:c:d (env)
+
+set FOO_PATH x y z
+echo $FOO_PATH           # x y z
+echo "$FOO_PATH"         # x:y:z
 

 
Command Handling

-
# sub-commands are not run in quotes
+
# sub-commands are not run in quotes
 echo "ls output: "(ls)
 

 
I/O redirection

-
# 'noclobber', fail if 'log' already exists
+
# 'noclobber', fail if 'log' already exists
 echo foo >? log
 

 
Control Flow

 
if / else

-
if grep foo bar
+
if grep foo bar
     # do sth
 else if grep foobar bar
     # do sth else
@@ -773,7 +778,7 @@ else
 end
 

 
switch

-
switch (echo foo)
+
switch (echo foo)
 case 'foo*'
     # do start with foo
 case bar dudel
@@ -783,18 +788,18 @@ case '*'
 end
 

 
while Loop

-
while true
+
while true
     echo foo
 end
 

 
for Loop

-
for f in (ls)
+
for f in (ls)
     echo $f
 end
 

 
Functions

 
Function arguments are passed via $argv list.

-
function fn_foo
+
function fn_foo
     echo $argv
 end
 

@@ -805,39 +810,116 @@ the function lazily if found.

 
This is the preferred way over monolithically defining all functions in a
 startup script.

 
Helper

-
functions         # list al functions
+
functions         # list al functions
 functions foo     # describe function 'foo'
 functions -e foo  # erase function 'foo'
 
 funced foo        # edit function 'foo'
                   # '-e vim' to edit in vim
 

+
Argument parsing and completion

+
argparse puts options into variables of name _flag_NAME.

+
References:

+
+
function moose --d "my moose fn"
+    # h/help   : short / long option (boolean)
+    # color    : only long option (boolean)
+    # u/user=  : option with required argument, only last specified is taken
+    # f/file+= : option with required argument, can be specified multiple times
+    #
+    argparse h/help color= u/user= f/file=+ -- $argv
+    or return
+
+    if set -ql _flag_help
+        echo "usage ..."
+        return 0
+    end
+
+    set -ql _flag_file
+    and echo "file=$_flag_file | cnt:" (count $_flag_file)
+
+    set -ql _flag_color
+    and echo "color=$_flag_color"
+
+    set -ql _flag_user
+    and echo "user=$_flag_user"
+end
+
+# Delete all previous defined completions for 'moose'.
+complete -c moose -e
+
+# Don't complete files for command.
+complete -c moose --no-files
+
+# Help completion.
+#   -n specifies a conditions. The completion is only active if the command
+#      returns 0.
+complete -c moose -s h -l help -n "not __fish_contains_opt -s h help" \
+    --description "Print usage help and exit"
+
+# File completion.
+#   -F force complete files (overwrite --no-files).
+#   -r requires argument.
+complete -c moose -s f -l file -F -r \
+    --description "Specify file (can be passed multiple times)"
+
+# Color completion.
+#    -a options for completion.
+#    -x short for -r and --no-files (-f)
+complete -c moose -x -l color -a "red blue" \
+    --description "Specify a color."
+
+# User completion.
+#    -a options for completion. Call a function to generate arguments.
+complete -c moose -x -s u -l user -a "(__fish_complete_users)" \
+    --description "Specify a user"
+

 
Prompt

 
The prompt is defined by the output of the fish_prompt function.

-
function fish_prompt
+
function fish_prompt
     set -l cmd_ret
     echo "> "(pwd) $cmd_ret" "
 end
 

 

-
Use set_color to manipulate terminal colors.

+
Use set_color to manipulate terminal colors and set_color -c to print the
+current colors.

 

 
Useful Builtins

-
# history
+
List all builtins with builtins -n.

+
# history
 history search <str>   # search history for <str>
 history merge          # merge histories from fish sessions
 
 # list
-count $var            # count elements in list
+count $var             # count elements in list
+
+contains /bin $PATH    # return 0 (true) 1 (false)
+contains -i /bin $PATH # additionally print index on stdout
 
 # string
 string split SEP STRING
+
+# math
+math -b hex 4096       # output dec as hex
+math 0x1000            # output hex as dec
+math "log2(1024)"      # call functions
+math -s0 7/3           # integer division (by default float)
+
+# status
+status -f              # abs path of current file
 

 
Keymaps

-
  Shift-Tab ........... tab-completion with search
-  Alt-Up / Alt-Down ... search history with token under the cursor
-  Alt-l ............... list content of dir under cursor
-  Alt-p ............... append '2>&1 | less;' to current cmdline
+
  Shift-Tab .............. tab-completion with search
+  Alt-Up / Alt-Down ...... search history with token under the cursor
+  Alt-l .................. list content of dir under cursor
+  Alt-p .................. append '2>&1 | less;' to current cmdline
+  Alt-Left / Alt - Right . prevd / nextd, walk dir history
 

 
Debug

 
  status print-stack-trace .. prints function stacktrace (can be used in scripts)
-- 
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