Project

General

Profile

Fhiclcpp types in detail » History » Version 33

Kyle Knoepfel, 11/17/2015 01:29 PM

1 1 Kyle Knoepfel
h1. @fhiclcpp@ types in detail
2 1 Kyle Knoepfel
3 20 Kyle Knoepfel
* [[Fhiclcpp_types_in_detail#ctors|Parameter constructors]]
4 16 Kyle Knoepfel
** [[Fhiclcpp_types_in_detail#ctors_rules|General rules]]
5 14 Kyle Knoepfel
** [[Fhiclcpp_types_in_detail#atom|Atom<T>]]
6 14 Kyle Knoepfel
** [[Fhiclcpp_types_in_detail#vector|Sequence<T>]]
7 14 Kyle Knoepfel
*** [[Fhiclcpp_types_in_detail#make_empty|make_empty()]]
8 27 Kyle Knoepfel
*** [[Fhiclcpp_types_in_detail#narrowing|Caveat regarding narrowing conversions]]
9 14 Kyle Knoepfel
** [[Fhiclcpp_types_in_detail#array|Sequence<T,std::size_t>]]
10 14 Kyle Knoepfel
** [[Fhiclcpp_types_in_detail#tuple|Tuple<T...>]]
11 14 Kyle Knoepfel
** [[Fhiclcpp_types_in_detail#table|Table<T>]]
12 9 Kyle Knoepfel
* [[Fhiclcpp_types_in_detail#return|Return types]]
13 22 Kyle Knoepfel
* [[Fhiclcpp_types_in_detail#table_func|Additional functions for Table<T>]]
14 22 Kyle Knoepfel
** [[Fhiclcpp_types_in_detail#get_pset|get_PSet]]
15 22 Kyle Knoepfel
** [[Fhiclcpp_types_in_detail#print|print_allowed_configuration]]
16 23 Kyle Knoepfel
** [[Fhiclcpp_types_in_detail#validate|validate_ParameterSet (*expert*)]]
17 14 Kyle Knoepfel
* [[Fhiclcpp_types_in_detail#common_acc|Common parameter accessors]]
18 1 Kyle Knoepfel
19 9 Kyle Knoepfel
----
20 9 Kyle Knoepfel
21 17 Kyle Knoepfel
h1(#ctors). Parameter constructors
22 1 Kyle Knoepfel
23 18 Kyle Knoepfel
h2(#ctors_rules). %{color:blue}General rules%
24 1 Kyle Knoepfel
25 1 Kyle Knoepfel
For each of the @fhiclcpp@ types, the following rules apply:
26 12 Kyle Knoepfel
* The @Name@ argument is required.
27 12 Kyle Knoepfel
* If there is more than one argument, the @Name@ argument must be first in the list.
28 12 Kyle Knoepfel
* If there are three arguments, the relative order of the @Comment@ argument and default-value argument is not important.
29 12 Kyle Knoepfel
<pre><code class="cpp">
30 12 Kyle Knoepfel
Atom<int> val { Name("val"), Comment("Some parameter"), 9 }; // is equivalent to
31 12 Kyle Knoepfel
Atom<int> val { Name("val"), 9, Comment("Some parameter") };
32 12 Kyle Knoepfel
</code></pre>
33 32 Kyle Knoepfel
* Neither the @Table<T>@ parameter nor any of the @Optional*@ parameters support a default value.
34 1 Kyle Knoepfel
35 18 Kyle Knoepfel
h2(#atom). %{color:blue}@Atom<T>@%
36 7 Kyle Knoepfel
37 1 Kyle Knoepfel
<pre><code class="cpp">
38 1 Kyle Knoepfel
Atom<int> var { Name("var") };
39 1 Kyle Knoepfel
Atom<int> var { Name("var"), 9 };
40 7 Kyle Knoepfel
Atom<int> var { Name("var"), Comment("A parameter description") };
41 1 Kyle Knoepfel
Atom<int> var { Name("var"), Comment("A parameter description"), 9 };
42 1 Kyle Knoepfel
</code></pre>
43 1 Kyle Knoepfel
44 33 Kyle Knoepfel
h2(#opt_atom). %{color:blue}@OptionalAtom<T>@%
45 33 Kyle Knoepfel
46 33 Kyle Knoepfel
<pre><code class="cpp">
47 33 Kyle Knoepfel
OptionalAtom<int> var { Name("var") };
48 33 Kyle Knoepfel
OptionalAtom<int> var { Name("var"), Comment("A parameter description") };
49 33 Kyle Knoepfel
</code></pre>
50 33 Kyle Knoepfel
51 33 Kyle Knoepfel
h2(#opt_vector). %{color:blue}@OptionalSequence<T>@%
52 33 Kyle Knoepfel
53 33 Kyle Knoepfel
This class template is used for unbounded sequences.  See the two caveats below.
54 33 Kyle Knoepfel
55 33 Kyle Knoepfel
<pre><code class="cpp">
56 33 Kyle Knoepfel
OptionalSequence<int> seq { Name("seq") };
57 33 Kyle Knoepfel
OptionalSequence<int> seq { Name("seq"), Comment("A sequence") };
58 33 Kyle Knoepfel
</code></pre>
59 33 Kyle Knoepfel
60 33 Kyle Knoepfel
h2(#opt_array). %{color:blue}@OptionalSequence<T,std::size_t>@%
61 33 Kyle Knoepfel
62 33 Kyle Knoepfel
This class template is used for sequences of a specific length, known at compile time.
63 33 Kyle Knoepfel
64 33 Kyle Knoepfel
<pre><code class="cpp">
65 33 Kyle Knoepfel
OptionalSequence<int,3u> seq { Name("seq") };
66 33 Kyle Knoepfel
OptionalSequence<int,3u> seq { Name("seq"), Comment("A sequence") };
67 33 Kyle Knoepfel
</code></pre>
68 33 Kyle Knoepfel
69 33 Kyle Knoepfel
h2(#opt_table). %{color:blue}@OptionalTable<T>@%
70 33 Kyle Knoepfel
71 33 Kyle Knoepfel
<pre><code class="cpp">
72 33 Kyle Knoepfel
OptionalTable<T> config { Name("config") };
73 33 Kyle Knoepfel
OptionalTable<T> config { Name("config"), Comment("This describes the table") };
74 33 Kyle Knoepfel
</code></pre>
75 33 Kyle Knoepfel
76 33 Kyle Knoepfel
h2(#opt_tuple). %{color:blue}@OptionalTuple<T...>@%
77 33 Kyle Knoepfel
78 33 Kyle Knoepfel
<pre><code class="cpp">
79 33 Kyle Knoepfel
OptionalTuple<string,bool> tuple { Name("tuple") };
80 33 Kyle Knoepfel
OptionalTuple<string,bool> tuple { Name("tuple"), Comment("A tuple") };
81 33 Kyle Knoepfel
</code></pre>
82 33 Kyle Knoepfel
83 18 Kyle Knoepfel
h2(#vector). %{color:blue}@Sequence<T>@%
84 1 Kyle Knoepfel
85 18 Kyle Knoepfel
This class template is used for unbounded sequences.  See the two caveats below.
86 18 Kyle Knoepfel
87 1 Kyle Knoepfel
<pre><code class="cpp">
88 7 Kyle Knoepfel
Sequence<int> seq { Name("seq") };
89 1 Kyle Knoepfel
Sequence<int> seq { Name("seq"), Comment("A sequence") };
90 1 Kyle Knoepfel
Sequence<int> seq { Name("seq"), Sequence<int>{ 4, 5, 6, 7 } };
91 1 Kyle Knoepfel
Sequence<int> seq { Name("seq"), { 4, 5, 6, 7 } };
92 1 Kyle Knoepfel
Sequence<int> seq { Name("seq"), Comment("A sequence"), Sequence<int>{ 4, 5, 6, 7 } };
93 1 Kyle Knoepfel
Sequence<int> seq { Name("seq"), Comment("A sequence"), { 4, 5, 6, 7 } };
94 1 Kyle Knoepfel
</code></pre>
95 1 Kyle Knoepfel
96 1 Kyle Knoepfel
h3(#make_empty). @Sequence<T>::make_empty()@
97 1 Kyle Knoepfel
98 8 Kyle Knoepfel
Due to the implementation details of the unbounded sequence, the following:
99 1 Kyle Knoepfel
100 8 Kyle Knoepfel
<pre><code class="cpp">
101 1 Kyle Knoepfel
Sequence<int> seq { Name("seq"), Sequence<int>{} }; // Don't do this.
102 1 Kyle Knoepfel
</code></pre>
103 1 Kyle Knoepfel
104 18 Kyle Knoepfel
_does not_ represent an empty sequence.  If you would like an empty sequence as a default value, use the following:
105 1 Kyle Knoepfel
106 1 Kyle Knoepfel
<pre><code class="cpp">
107 1 Kyle Knoepfel
Sequence<int> seq { Name("seq"), Sequence<int>::make_empty() };
108 1 Kyle Knoepfel
</code></pre>
109 1 Kyle Knoepfel
110 18 Kyle Knoepfel
h3(#narrowing). Precaution regarding narrowing conversions and @std::initializer_list@ objects
111 1 Kyle Knoepfel
112 19 Kyle Knoepfel
The following configuration will trigger a compilation warning:
113 19 Kyle Knoepfel
114 19 Kyle Knoepfel
<pre><code class="cpp">
115 19 Kyle Knoepfel
Sequence<int> seq1 { Name("seq1"), Sequence<int>{ 1, 2.4e-4 } };
116 19 Kyle Knoepfel
Sequence<int> seq2 { Name("seq2"), { 1, 2.4e-4 } };
117 19 Kyle Knoepfel
</code></pre>
118 19 Kyle Knoepfel
119 19 Kyle Knoepfel
that looks similar to this:
120 18 Kyle Knoepfel
121 18 Kyle Knoepfel
<pre>
122 18 Kyle Knoepfel
warning: narrowing conversion of ‘2.4000000000000001e-4’ from ‘double’ to ‘int’ inside { } [-Wnarrowing]
123 18 Kyle Knoepfel
</pre>
124 1 Kyle Knoepfel
125 1 Kyle Knoepfel
For build systems that convert compile-time warnings to errors, this will result in a build failure.  The warning results from the nature of an @std::initializer_list@ object, signified by @'{1, 2.4e-4}'@, which is used to initialize the sequence objects.  For @std::initializer_list@ objects, narrowing conversions are not allowed--that is, converting a @double@ to an @int@ is an example of narrowing that results in loss of information.  This is the most likely example of where you may find a narrowing conversion.
126 1 Kyle Knoepfel
127 1 Kyle Knoepfel
h2(#array). %{color:blue}@Sequence<T,std::size_t>@%
128 1 Kyle Knoepfel
129 1 Kyle Knoepfel
This class template is used for sequences of a specific length, known at compile time.
130 1 Kyle Knoepfel
131 1 Kyle Knoepfel
<pre><code class="cpp">
132 1 Kyle Knoepfel
Sequence<int,3u> seq { Name("seq") };
133 18 Kyle Knoepfel
Sequence<int,3u> seq { Name("seq"), Comment("A sequence") };
134 17 Kyle Knoepfel
Sequence<int,3u> seq { Name("seq"), Sequence<int,3u>{ 4, 5, 6 } };
135 18 Kyle Knoepfel
Sequence<int,3u> seq { Name("seq"), { 4, 5, 6 } };
136 18 Kyle Knoepfel
Sequence<int,3u> seq { Name("seq"), Comment("A sequence"), Sequence<int,3u>{ 4, 5, 6 } };
137 1 Kyle Knoepfel
Sequence<int,3u> seq { Name("seq"), Comment("A sequence"), { 4, 5, 6 } };
138 1 Kyle Knoepfel
</code></pre>
139 1 Kyle Knoepfel
140 1 Kyle Knoepfel
The warning regarding narrowing conversions [[Fhiclcpp_types_in_detail#narrowing|above]] applies for bounded sequences as well.
141 1 Kyle Knoepfel
142 33 Kyle Knoepfel
h2(#table). %{color:blue}@Table<T>@%
143 33 Kyle Knoepfel
144 33 Kyle Knoepfel
<pre><code class="cpp">
145 33 Kyle Knoepfel
Table<T> config { Name("config") };
146 33 Kyle Knoepfel
Table<T> config { Name("config"), Comment("This describes the table") };
147 33 Kyle Knoepfel
</code></pre>
148 33 Kyle Knoepfel
149 1 Kyle Knoepfel
h2(#tuple). %{color:blue}@Tuple<T...>@%
150 1 Kyle Knoepfel
151 1 Kyle Knoepfel
<pre><code class="cpp">
152 1 Kyle Knoepfel
Tuple<string,bool> tuple { Name("tuple") };
153 18 Kyle Knoepfel
Tuple<string,bool> tuple { Name("tuple"), Comment("A tuple") };
154 1 Kyle Knoepfel
Tuple<string,bool> tuple { Name("tuple"), Tuple<string,bool>{"explicit?", true} };
155 1 Kyle Knoepfel
Tuple<string,bool> tuple { Name("tuple"), {"compact?", true } };
156 1 Kyle Knoepfel
Tuple<string,bool> tuple { Name("tuple"), Comment("A tuple"), Tuple<string,bool>{ "Particle physics is neat.", true } };
157 1 Kyle Knoepfel
Tuple<string,bool> tuple { Name("tuple"), Comment("A tuple"), { "This is false", false } };
158 1 Kyle Knoepfel
</code></pre>
159 1 Kyle Knoepfel
160 1 Kyle Knoepfel
----
161 1 Kyle Knoepfel
162 17 Kyle Knoepfel
h1(#return). Return types
163 1 Kyle Knoepfel
164 1 Kyle Knoepfel
|{background:#fba}. *@fhiclcpp@ parameter*|{background:#fba}. *Function call*|{background:#fba}. *Return type*|
165 1 Kyle Knoepfel
|\3{background:#ddd}. _Simple @fhiclcpp@ parameters_|
166 1 Kyle Knoepfel
|@Atom<std::string> label@; |@label()@| @std::string const&@|
167 1 Kyle Knoepfel
|/2.@Sequence<int> counts@; | @counts()@ | @std::vector<int>@|
168 1 Kyle Knoepfel
|@counts(1)@ | @int@ |
169 1 Kyle Knoepfel
|/2.@Sequence<double, 3u> point@;| @point()@ | @std::array<double, 3u>@|
170 1 Kyle Knoepfel
|@point(0)@ | @double@ |
171 1 Kyle Knoepfel
|/3.@Tuple<std::string, double> assoc;@|@assoc()@| @std::tuple<std::string, double>@|
172 1 Kyle Knoepfel
|@assoc.get<0>()@|@std::string@|
173 1 Kyle Knoepfel
|@assoc.get<double>()@|@double@|
174 8 Kyle Knoepfel
|@Table<Config> config;@|@config()@|@Config const&@|
175 8 Kyle Knoepfel
|\3{background:#ddd}. _Nested @fhiclcpp@ parameters_|
176 8 Kyle Knoepfel
|/2.@Sequence< Sequence<int> > datasets;@ | @datasets()@ | @std::vector< std::vector<int> >@ |
177 8 Kyle Knoepfel
| @datasets(17)@ | @std::vector<int>@ |
178 8 Kyle Knoepfel
|/2.@Sequence< Sequence<int>, 2u > twoDatasets;@ | @twoDatasets()@ | @std::array< std::vector<int>, 2u >@ |
179 8 Kyle Knoepfel
|@twoDatasets(1)@ | @std::vector<int>@ |
180 8 Kyle Knoepfel
|/2.@Sequence< Sequence<int, 2u> > intPairs;@ | @intPairs()@ | @std::vector< std::array<int, 2u> >@ |
181 8 Kyle Knoepfel
|@intPairs(42)@ | @std::array<int, 2u>@|
182 8 Kyle Knoepfel
|/2.@Sequence< Tuple<std::string, int, bool> > triplets;@ | @triplets()@ | @std::vector< std::tuple<std::string, int, bool> >@ |
183 1 Kyle Knoepfel
|@triplets(3)@ | @std::tuple<std::string, int, bool>@ |
184 1 Kyle Knoepfel
|/2.@Sequence< Table<Config> > manyConfigTables;@ | @manyConfigTables()@ | @std::vector< Config >@ |
185 7 Kyle Knoepfel
|@manyConfigTables(6)@ | @Config const&@ |
186 1 Kyle Knoepfel
|/5.@Tuple< std::string, Table<Config> > configAssoc;@ | @configAssoc()@ | @std::tuple< std::string, Config >@ |
187 7 Kyle Knoepfel
|@configAssoc.get<0>()@ | @std::string@ |
188 10 Kyle Knoepfel
|@configAssoc.get<std::string>()@ | @std::string@ |
189 10 Kyle Knoepfel
|@configAssoc.get<1>()@ | @Config@ |
190 11 Kyle Knoepfel
|@configAssoc.get< Table<Config> >()@ | @Config@ |
191 10 Kyle Knoepfel
|/3.@Tuple< Tuple<std::string,bool>, Sequence<int> > awkward;@ | @awkward()@ | @std::tuple< std::tuple<std::string, bool>, std::vector<int> >@ |
192 10 Kyle Knoepfel
|@awkward.get<0>()@|@std::tuple<std::string,bool>@|
193 14 Kyle Knoepfel
|@awkward.get<1>()@|@std::vector<int>@|
194 14 Kyle Knoepfel
195 14 Kyle Knoepfel
----
196 1 Kyle Knoepfel
197 22 Kyle Knoepfel
h1(#table_func). Additional functions for @Table<T>@
198 21 Kyle Knoepfel
199 21 Kyle Knoepfel
The @Table@ template offers a few extra functions that the user can call: 
200 21 Kyle Knoepfel
201 21 Kyle Knoepfel
<pre><code class="cpp">
202 21 Kyle Knoepfel
fhicl::ParameterSet const& get_PSet() const;
203 21 Kyle Knoepfel
204 21 Kyle Knoepfel
void print_allowed_configuration(std::ostream& os,
205 21 Kyle Knoepfel
                                 std::string const& tab = std::string(3,' ') ) const;
206 21 Kyle Knoepfel
207 21 Kyle Knoepfel
// Expert-level functions
208 21 Kyle Knoepfel
void validate_ParameterSet(fhicl::ParameterSet const& pset,
209 21 Kyle Knoepfel
                           std::set<std::string> const& keysToIgnore = {} );
210 21 Kyle Knoepfel
211 21 Kyle Knoepfel
</code></pre>
212 21 Kyle Knoepfel
213 21 Kyle Knoepfel
h3(#get_pset). @get_PSet@
214 21 Kyle Knoepfel
215 21 Kyle Knoepfel
A call to this function returns a @const@ reference to the @ParameterSet@ object that was used to fill the values of the individual @Table@ members.  This is helpful for users who need to interact with the @ParameterSet@ object itself.
216 21 Kyle Knoepfel
217 21 Kyle Knoepfel
h3(#print). @print_allowed_configuration@
218 21 Kyle Knoepfel
219 21 Kyle Knoepfel
For any @Table<Config>@ object, @print_allowed_configuration@ will fill a user-supplied @std::ostream@ object with the allowed configuration as defined by the @Config@ struct.  The optional second argument specifies the number of spaces per indentation.  The default is 3 spaces but is, of course, user-configurable.
220 21 Kyle Knoepfel
221 24 Kyle Knoepfel
----
222 1 Kyle Knoepfel
223 28 Kyle Knoepfel
%{color:red} _[ *N.B.* The following function should not normally be invoked by users. It is meant to be called only in contexts outside of @art@.  Please consult artists@fnal.gov for guidance.]_%
224 24 Kyle Knoepfel
225 21 Kyle Knoepfel
h3(#validate). @validate_ParameterSet@ (expert)
226 21 Kyle Knoepfel
227 1 Kyle Knoepfel
This function is intended for experts who need to validate the @pset@ object themselves.  The @keysToIgnore@ variable represents a set of keys for which the validation step will ignore.  The validation function will ignore any nested keys as well--i.e. if a user specifies an ignorable key as @table1@, the (e.g.) @table1.someAtom@ key would be ignored in addition to just the @table1@ name.  An indexed parameter (e.g.) @seq[1]@ is considered a nested parameter of its parent @seq@.  Providing or not providing the ignorable key in a configuration will lead to no error upon validation of the @ParameterSet@.
228 21 Kyle Knoepfel
229 24 Kyle Knoepfel
Should the validation step fail, an exception is thrown of type @fhicl::detail::validationException@.  This behavior is not currently configurable.
230 21 Kyle Knoepfel
231 25 Kyle Knoepfel
----
232 25 Kyle Knoepfel
233 17 Kyle Knoepfel
h1(#common_acc). Common parameter accessors
234 14 Kyle Knoepfel
235 14 Kyle Knoepfel
Each of the @fhiclcpp@ types has the following accessors:
236 14 Kyle Knoepfel
<pre><code class="cpp">
237 14 Kyle Knoepfel
std::string key()            const;
238 30 Kyle Knoepfel
std::string name()           const;
239 14 Kyle Knoepfel
std::string comment()        const;
240 14 Kyle Knoepfel
bool        has_default()    const;
241 30 Kyle Knoepfel
bool        is_optional()    const;
242 14 Kyle Knoepfel
par_type    parameter_type() const;
243 14 Kyle Knoepfel
</code></pre>
244 14 Kyle Knoepfel
245 14 Kyle Knoepfel
To call these functions, the difference in syntax is crucial:
246 14 Kyle Knoepfel
247 14 Kyle Knoepfel
<pre><code class="cpp">
248 14 Kyle Knoepfel
Atom<int> val { Name("val") };
249 14 Kyle Knoepfel
250 14 Kyle Knoepfel
auto key1 = val.key();   //   correct
251 14 Kyle Knoepfel
auto key2 = val().key(); // ! compile-time ERROR - 'val()' is an int, which has no accessor called 'key()' 
252 14 Kyle Knoepfel
</code></pre>
253 14 Kyle Knoepfel
254 17 Kyle Knoepfel
h2. @key()@
255 14 Kyle Knoepfel
256 14 Kyle Knoepfel
A call to @key()@ returns the _full_ key, including all enclosing tables.  For example, consider a module that is designed to allow the following configuration:
257 14 Kyle Knoepfel
<pre><code class="ruby">
258 14 Kyle Knoepfel
pset: {
259 14 Kyle Knoepfel
  list: [ { particle: electron },
260 14 Kyle Knoepfel
          { particle: muon } ]
261 14 Kyle Knoepfel
}
262 31 Kyle Knoepfel
</code></pre>For a suitably declared set of @fhiclcpp@ parameters, the returned key corresponding to "muon" would be @pset.list[1].particle@.
263 1 Kyle Knoepfel
264 30 Kyle Knoepfel
h2. @name()@
265 14 Kyle Knoepfel
266 30 Kyle Knoepfel
The name is the most-nested name in the key.  For the above "muon" parameter, a key of @pset.list[1].particle@ has a corresponding name of @particle@.  If the parameter in question were @pset.list[1]@, the name would be[1] @list[1]@.
267 1 Kyle Knoepfel
268 30 Kyle Knoepfel
fn1. Technically, this is inaccurate -- sequence elements do not have names.  However, for the sake of parameter identification, a sequence element has a name whose value is the sequence name with the appropriate sequence element index/indices appended.
269 30 Kyle Knoepfel
270 17 Kyle Knoepfel
h2. @comment()@
271 14 Kyle Knoepfel
272 14 Kyle Knoepfel
Returns the comment supplied as the string literal in (e.g.) @Comment("Here is the comment")@.  If no @Comment@ argument is provided in the @fhiclcpp@ parameter constructor, a call to this function returns an empty string.
273 14 Kyle Knoepfel
274 17 Kyle Knoepfel
h2. @has_default()@
275 14 Kyle Knoepfel
276 1 Kyle Knoepfel
Returns @true@ or @false@ depending on whether the user supplied a default value for the parameter.
277 1 Kyle Knoepfel
278 30 Kyle Knoepfel
h2. @is_optional()@
279 30 Kyle Knoepfel
280 30 Kyle Knoepfel
Returns @true@ or @false@ depending on whether the parameter is of an @Optional*@ @fhiclcpp@ type.
281 30 Kyle Knoepfel
282 1 Kyle Knoepfel
h2. @parameter_type()@
283 1 Kyle Knoepfel
284 1 Kyle Knoepfel
Returns an enumeration value based on the parameter type:
285 1 Kyle Knoepfel
286 14 Kyle Knoepfel
<pre><code class="cpp">
287 14 Kyle Knoepfel
enum class par_type {
288 30 Kyle Knoepfel
  ATOM,        // (Optional)Atom<T>
289 30 Kyle Knoepfel
  TABLE,       // (Optional)Table<T>
290 30 Kyle Knoepfel
  SEQ_VECTOR,  // (Optional)Sequence<T>
291 30 Kyle Knoepfel
  SEQ_ARRAY,   // (Optional)Sequence<T,std::size_t>
292 30 Kyle Knoepfel
  TUPLE,       // (Optional)Tuple<T...>
293 14 Kyle Knoepfel
  NTYPES       // Signifies invalid parameter 
294 14 Kyle Knoepfel
};
295 14 Kyle Knoepfel
</code></pre>