Git like subcommands

Your CLI app can gain git-like subcommands by using the dispatchMulti macro.

Here's an example where the app has subcommands one and two.

• Assign a separate proc for each subcommand.
  • Name the proc with the name you want to give to the subcommand (this is not necessary, but suggesting this for simplicity of this example).
• Pass the "subcommand proc" identifiers or symbols to the dispatchMulti.

proc one(args: seq[string];   # variable number of "non switch type" string args
         foo: bool) =         # a mandatory bool switch
  echo "args = ", args, " foo = ", foo

proc two(boolS = true; # an optional bool switch with a default value
         intS = 123) = # an optional int switch with a default value
  echo "boolS = ", boolS, " intS = ", intS

when isMainModule:
  import cligen
  dispatchMulti(
    [one],
    [two]
  )

Let's name the above file t.nim. On Unix systems, on compiling it, you'll get an executable named t.

Here are some ways in which this CLI app will work with subcommands:

> ./t one --foo
args = @[] foo = true

> ./t one --foo:true  
args = @[] foo = true

> ./t one -f:false 
args = @[] foo = false

> ./t o --fo:off
args = @[] foo = false

> ./t one abc def -f
args = @["abc", "def"] foo = true

> ./t two
boolS = true intS = 123

> ./t two -b:false
boolS = false intS = 123

> ./t two -i:999 -b
boolS = false intS = 999

> ./t tw -bi999
boolS = false intS = 999