diff options
Diffstat (limited to 'examples')
| -rw-r--r-- | examples/how_do_i.nom | 30 |
1 files changed, 18 insertions, 12 deletions
diff --git a/examples/how_do_i.nom b/examples/how_do_i.nom index 9645be1..edd226a 100644 --- a/examples/how_do_i.nom +++ b/examples/how_do_i.nom @@ -302,36 +302,42 @@ debug only: # How do I use an action as a value? # Well... it's always *possible* to fall back to Lua behavior for something like this: (best of $items according to $key_fn) means: - $best = (nil) - $best_key = (nil) + [$best, $best_key] = [nil, nil] for $item in $items: $key = ($key_fn $item) if (($best is (nil)) or ($key > $best_key)): - $best = $item - $best_key = $key + [$best, $best_key] = [$item, $key] return $best # Function literals look like: $x -> ($x * $x) say (best of [2, -3, 4, -8] according to ($x -> ($x * $x))) -# Or, you can use $(foo $) to access the function that gets called by (foo $) +# Or, you can surround an action with $(...) to refer to it: ($x squared) means ($x * $x) say (best of [2, -3, 4, -8] according to $($ squared)) -# But nomsu was designed with flexible alternatives that are often better than passing functions. - For example, instead of calling a key function on every item, you could instead define a macro - that gives you a value based on an inlined expression: +# However, nomsu was designed with flexible alternatives that are often better + than passing functions. For example, instead of calling a key function on + every item, you could instead define a macro that will inline an expression + to produce faster code: (best of $items where $item has score $key_expr) parses as result of: - $best = (nil) - $best_key = (nil) + [$best, $best_key] = [nil, nil] for $item in $items: $key = $key_expr if (($best is (nil)) or ($key > $best_key)): - $best = $item - $best_key = $key + [$best, $best_key] = [$item, $key] return $best ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ say (best of [2, -3, 4, -8] where $x has score ($x * $x)) +# The line above expands to: +say + result of: + [$best, $best_key] = [nil, nil] + for $x in [2, -3, 4, -8]: + $key = ($x * $x) + if (($best is (nil)) or ($key > $best_key)): + [$best, $best_key] = [$x, $key] + return $best |