Fuzion • Idioms • Idiom # 206: Switch statement with strings

Idiom # 206: Switch statement with strings

Code

((container.ordered_map ["foo",   "bar",   "baz",   "barfl"  ]
                        [foo, bar, baz, barfl])[str].unwrap.call)

# NYI: This will need some syntax improvements:
#
#      1. better syntax for inline maps
#      2. better syntax for inline funtions
#      3. automatic unwrap and call
#
# example:
#
#   switch str ["foo"   => foo
#               "bar"   => bar
#               "baz"   => baz
#               "barfl" => barfl]
#
# where 'switch' is a feature declared similar to
#
#  switch<T, U> (on T, m map<T, () -> U) =>
#    m[on].unwrap.call
#

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((container.ordered_map ["foo",   "bar",   "baz",   "barfl"  ]
                        [foo, bar, baz, barfl])[str].unwrap.call)
# NYI: This will need some syntax improvements:
#
#      1. better syntax for inline maps
#      2. better syntax for inline funtions
#      3. automatic unwrap and call
#
# example:
#
#   switch str ["foo"   => foo
#               "bar"   => bar
#               "baz"   => baz
#               "barfl" => barfl]
#
# where 'switch' is a feature declared similar to
#
#  switch<T, U> (on T, m map<T, () -> U) =>
#    m[on].unwrap.call
#
 
 
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What are effects?

Running Example

ex206 is

  foo Function unit => ()->say "foo"
  bar Function unit => ()->say "bar"
  baz Function unit => ()->say "baz"
  barfl Function unit => ()->say "barfl"

  for str in ["bar",
              "foo",
              "barfl",
              "baz",
              "error" /* will cause a precondition failure! */]
  do
    ((container.ordered_map ["foo",   "bar",   "baz",   "barfl"  ]
                            [foo, bar, baz, barfl])[str].get.call)

# NYI: better syntax, e.g.,
#
#   switch str ["foo"   => foo
#               "bar"   => bar
#               "baz"   => baz
#               "barfl" => barfl]

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ex206 is
  foo Function unit => ()->say "foo"
  bar Function unit => ()->say "bar"
  baz Function unit => ()->say "baz"
  barfl Function unit => ()->say "barfl"
  for str in ["bar",
              "foo",
              "barfl",
              "baz",
              "error" /* will cause a precondition failure! */]
  do
    ((container.ordered_map ["foo",   "bar",   "baz",   "barfl"  ]
                            [foo, bar, baz, barfl])[str].get.call)
# NYI: better syntax, e.g.,
#
#   switch str ["foo"   => foo
#               "bar"   => bar
#               "baz"   => baz
#               "barfl" => barfl]
 
 
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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What are effects?

last changed: 2025-05-13

next: Idiom # 207: allocate a list that is automatically deallocated