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+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+ Package template implements data-driven templates for generating textual
+ output such as HTML.
+
+ Templates are executed by applying them to a data structure.
+ Annotations in the template refer to elements of the data
+ structure (typically a field of a struct or a key in a map)
+ to control execution and derive values to be displayed.
+ The template walks the structure as it executes and the
+ "cursor" @ represents the value at the current location
+ in the structure.
+
+ Data items may be values or pointers; the interface hides the
+ indirection.
+
+ In the following, 'Field' is one of several things, according to the data.
+
+ - The name of a field of a struct (result = data.Field),
+ - The value stored in a map under that key (result = data["Field"]), or
+ - The result of invoking a niladic single-valued method with that name
+ (result = data.Field())
+
+ If Field is a struct field or method name, it must be an exported
+ (capitalized) name.
+
+ Major constructs ({} are the default delimiters for template actions;
+ [] are the notation in this comment for optional elements):
+
+ {# comment }
+
+ A one-line comment.
+
+ {.section field} XXX [ {.or} YYY ] {.end}
+
+ Set @ to the value of the field. It may be an explicit @
+ to stay at the same point in the data. If the field is nil
+ or empty, execute YYY; otherwise execute XXX.
+
+ {.repeated section field} XXX [ {.alternates with} ZZZ ] [ {.or} YYY ] {.end}
+
+ Like .section, but field must be an array or slice. XXX
+ is executed for each element. If the array is nil or empty,
+ YYY is executed instead. If the {.alternates with} marker
+ is present, ZZZ is executed between iterations of XXX.
+
+ {field}
+ {field1 field2 ...}
+ {field|formatter}
+ {field1 field2...|formatter}
+ {field|formatter1|formatter2}
+
+ Insert the value of the fields into the output. Each field is
+ first looked for in the cursor, as in .section and .repeated.
+ If it is not found, the search continues in outer sections
+ until the top level is reached.
+
+ If the field value is a pointer, leading asterisks indicate
+ that the value to be inserted should be evaluated through the
+ pointer. For example, if x.p is of type *int, {x.p} will
+ insert the value of the pointer but {*x.p} will insert the
+ value of the underlying integer. If the value is nil or not a
+ pointer, asterisks have no effect.
+
+ If a formatter is specified, it must be named in the formatter
+ map passed to the template set up routines or in the default
+ set ("html","str","") and is used to process the data for
+ output. The formatter function has signature
+ func(wr io.Writer, formatter string, data ...interface{})
+ where wr is the destination for output, data holds the field
+ values at the instantiation, and formatter is its name at
+ the invocation site. The default formatter just concatenates
+ the string representations of the fields.
+
+ Multiple formatters separated by the pipeline character | are
+ executed sequentially, with each formatter receiving the bytes
+ emitted by the one to its left.
+
+ As well as field names, one may use literals with Go syntax.
+ Integer, floating-point, and string literals are supported.
+ Raw strings may not span newlines.
+
+ The delimiter strings get their default value, "{" and "}", from
+ JSON-template. They may be set to any non-empty, space-free
+ string using the SetDelims method. Their value can be printed
+ in the output using {.meta-left} and {.meta-right}.
+*/
+package template