Arg::env

env

since 0.1.0

Read from name environment variable when argument is not present.

Examples

Example 1

Spec

TOML

name = "prog"
[args]
flag = { long = "flag", env = "MY_FLAG", action = "set", default-value = "default" }

YAML

name: prog
args:
  flag:
    long: flag
    env: MY_FLAG
    action: set
    default-value: default

JSON

{
  "name": "prog",
  "args": {
    "flag": {
      "long": "flag",
      "env": "MY_FLAG",
      "action": "set",
      "default-value": "default"
    }
  }
}

Input

prog

Output

claptrap_flag='env'

Example 2

Spec

TOML

name = "prog"
[args]
true_flag = { long = "true_flag", env = "TRUE_FLAG", action = "set-true", value-parser = [":falsey:"] }
false_flag = { long = "false_flag", env = "FALSE_FLAG", action = "set-true", value-parser = [":falsey:"] }
absent_flag = { long = "absent_flag", env = "ABSENT_FLAG", action = "set-true", value-parser = [":falsey:"] }

YAML

name: prog
args:
  true_flag:
    long: true_flag
    env: TRUE_FLAG
    action: set-true
    value-parser:
    - ':falsey:'
  false_flag:
    long: false_flag
    env: FALSE_FLAG
    action: set-true
    value-parser:
    - ':falsey:'
  absent_flag:
    long: absent_flag
    env: ABSENT_FLAG
    action: set-true
    value-parser:
    - ':falsey:'

JSON

{
  "name": "prog",
  "args": {
    "true_flag": {
      "long": "true_flag",
      "env": "TRUE_FLAG",
      "action": "set-true",
      "value-parser": [
        ":falsey:"
      ]
    },
    "false_flag": {
      "long": "false_flag",
      "env": "FALSE_FLAG",
      "action": "set-true",
      "value-parser": [
        ":falsey:"
      ]
    },
    "absent_flag": {
      "long": "absent_flag",
      "env": "ABSENT_FLAG",
      "action": "set-true",
      "value-parser": [
        ":falsey:"
      ]
    }
  }
}

Input

prog

Output

claptrap_true_flag='true'
claptrap_false_flag='false'
claptrap_absent_flag='false'

Example 3

Spec

TOML

name = "prog"
[args]
flag = { long = "flag", env = "MY_FLAG_MULTI", action = "set", num-args = "1..", value-delimiter = "," }

YAML

name: prog
args:
  flag:
    long: flag
    env: MY_FLAG_MULTI
    action: set
    num-args: 1..
    value-delimiter: ','

JSON

{
  "name": "prog",
  "args": {
    "flag": {
      "long": "flag",
      "env": "MY_FLAG_MULTI",
      "action": "set",
      "num-args": "1..",
      "value-delimiter": ","
    }
  }
}

Input

prog

Output

claptrap_flag=('env1' 'env2')

Example 4

Spec

TOML

name = "prog"
[args]
flag = { long = "flag", env = "MY_FLAG", action = "set" }

YAML

name: prog
args:
  flag:
    long: flag
    env: MY_FLAG
    action: set

JSON

{
  "name": "prog",
  "args": {
    "flag": {
      "long": "flag",
      "env": "MY_FLAG",
      "action": "set"
    }
  }
}

Input

prog --flag opt

Output

claptrap_flag='opt'

Example 5

Spec

TOML

name = "prog"
[args]
flag = { long = "flag", env = "MY_FLAG", action = "set" }

YAML

name: prog
args:
  flag:
    long: flag
    env: MY_FLAG
    action: set

JSON

{
  "name": "prog",
  "args": {
    "flag": {
      "long": "flag",
      "env": "MY_FLAG",
      "action": "set"
    }
  }
}

Input

prog

Output

claptrap_flag='env'