more fundamental changes
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README.md
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README.md
@ -59,49 +59,50 @@ This evaluates to list whose elements are a function and two numbers:
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(":+" 1 2)
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```
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A list prefixed with a `:` calls the first element as a function with the rest
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of the elements as arguments. This evaluates to the number 5:
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A list whose first element is a `:` calls the second element as a function with
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the rest of the elements as arguments. This evaluates to the number 5:
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```
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:(":+" 1 2)
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(":" ":+" 1 2)
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```
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A bare string (lacking in `"`) is a shortcut for that string prefixed by a `:`.
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This is equivalent to the above:
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A bare `:` or `.` string (lacking in `"`) is a shortcut for `":"` or `"."`,
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respectively. An otherwise bare string is a shortcut for that string prefixed by
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a `:`. This is equivalent to the previous example:
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```
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:(+ 1 2)
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(: + 1 2)
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```
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The `fn` function can be used to define a new function. This evaluates to an
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anonymous function which adds one to its argument and returns it:
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The `fn` function can be used to define a new function. Note the `.` instead of
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`:`. We'll cover that in a bit. This evaluates to an anonymous function which
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adds one to its argument and returns it:
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```
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:(fn [x]
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:(+ x 1))
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(. fn [x]
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(: + x 1))
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```
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The `def` function can be used to bind some value to a new variable. Note the
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`.` instead of `:`. We'll cover that in a bit. This defines a variable `foo`
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which evaluates to the string `"bar"`:
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The `def` function can be used to bind some value to a new variable. This
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defines a variable `foo` which evaluates to the string `"bar"`:
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```
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.(def foo "bar")
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(. def foo "bar")
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```
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This defines a variable `incr` which evaluates to a function which adds one to
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its argument:
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```
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.(def incr
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:(fn [x]
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:(+ x 1)))
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(. def incr
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(. fn [x]
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(: + x 1)))
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```
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This uses `defn` as a shortcut for the above:
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```
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.(defn incr [x]
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:(+ x 1))
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(. defn incr [x]
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(: + x 1))
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```
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There are also maps. A map's keys can be any value(?). A map's values can be any
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@ -109,28 +110,35 @@ value. This evaluates to a map with 2 key/val pairs:
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```
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{ "foo" foo
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"bar" :(incr 4) }
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"bar" (: incr 4) }
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```
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`.` is the half-evaluator. It only works on lists, and runs the function given
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in the first argument with the unevaluated arguments (even if they have `:` in
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front). You can generate new code to run on the fly (macros) using the normal
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`fn`. This evaluates to a `let`-like function, except it forces you to use the
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capitalized variable names in the body (utterly useless):
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in the first argument with the unevaluated arguments (even if they have `:`).
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You can generate new code to run on the fly (macros) using the normal `fn`. This
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evaluates to a `let`-like function, except it forces you to use the capitalized
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variable names in the body (utterly useless):
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```
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.(defn caplet [mapping body...]
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#
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# eval evaluates a given value (either a string or list). It has been
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# implicitely called on all examples so far.
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#
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# elem-map maps over every element in a list, embedded or otherwise
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::(elem-map
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:(fn [x]
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:(if (mapping :(slice x 1))
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(capitalize x)
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#
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# capitalize looks for the first letter in a string and capitalizes it
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#
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(. defn caplet [mapping body...]
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(. eval (: elem-map
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(. fn [x]
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(. if (: mapping (: slice x 1))
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(: capitalize x)
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x))
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body))
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#Usage
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.(caplet [foo "this is foo"
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(. caplet [foo "this is foo"
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dog "this is dog"]
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:(println Foo)
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:(println Dog))
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(: println Foo)
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(: println Dog))
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```
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