Add licensing info and package level docs

LICENSE

@@ -0,0 +1,24 @@
+Copyright (c) 2020 Denis Bernard <[email protected]>. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

LICENSE-go

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+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

dec.go

@@ -1,3 +1,7 @@
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 package decimal
 
 import (

dec_arith.go

@@ -1,3 +1,7 @@
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 package decimal
 
 import (

dec_arith_amd64.s

@@ -1,4 +1,4 @@
-// Copyright 2009 The Go Authors. All rights reserved.
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 

dec_arith_decl.go

@@ -1,3 +1,7 @@
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 // +build !decimal_pure_go,amd64
 
 package decimal

dec_arith_decl_pure.go

@@ -1,3 +1,7 @@
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 // +build decimal_pure_go !amd64
 
 package decimal

dec_arith_test.go

@@ -1,3 +1,7 @@
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 package decimal
 
 import (

dec_conv.go

@@ -1,3 +1,7 @@
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 package decimal
 
 import (

dec_conv_test.go

@@ -1,4 +1,4 @@
-// Copyright 2015 The Go Authors. All rights reserved.
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 

dec_test.go

@@ -1,4 +1,4 @@
-// Copyright 2009 The Go Authors. All rights reserved.
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 

decimal.go

@@ -1,3 +1,7 @@
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 package decimal
 
 import (

decimal_conv.go

@@ -1,3 +1,7 @@
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 package decimal
 
 import (

decimal_marsh.go

@@ -1,4 +1,4 @@
-// Copyright 2015 The Go Authors. All rights reserved.
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 

decimal_sqrt.go

@@ -1,3 +1,7 @@
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 package decimal
 
 import (

decimal_test.go

@@ -1,3 +1,7 @@
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 package decimal
 
 import (

decimal_toa.go

@@ -1,4 +1,4 @@
-// Copyright 2015 The Go Authors. All rights reserved.
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 

doc.go

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+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package decimal implements arbitrary-precision decimal floating-point
+arithmetic.
+
+The implementation is heavily based on big.Float and besides a few additional
+getters and setters for other math/big types, the API is identical to that of
+*big.Float.
+
+Howvever, and unlike big.Float, the mantissa of a decimal is stored in a
+little-endian Word slice as "declets" of 9 or 19 decimal digits per 32 or 64
+bits Word. All arithmetic operations are performed directly in base 10**9 or
+10**19 without conversion to/from binary.
+
+The zero value for a Decimal corresponds to 0. Thus, new values can be declared
+in the usual ways and denote 0 without further initialization:
+
+    x := new(Decimal)  // x is a *Decimal of value 0
+
+Alternatively, new Decimal values can be allocated and initialized with the
+function:
+
+    func NewDecimal(f float64) *Decimal
+
+For instance, NewDecimal(x) returns a *Decimal set to the value of the float64
+argument f. More flexibility is provided with explicit setters, for instance:
+
+    z := new(Float).SetUint64(123)    // z3 := 123.0
+
+Setters, numeric operations and predicates are represented as methods of the
+form:
+
+    func (z *Decimal) SetV(v V) *Decimal                // z = v
+    func (z *Decimal) Unary(x *Decimal) *Decimal        // z = unary x
+    func (z *Decimal) Binary(x, y *Decimal) *Decimal    // z = x binary y
+    func (x *Decimal) Pred() P                          // p = pred(x)
+
+For unary and binary operations, the result is the receiver (usually named z in
+that case; see below); if it is one of the operands x or y it may be safely
+overwritten (and its memory reused).
+
+Arithmetic expressions are typically written as a sequence of individual method
+calls, with each call corresponding to an operation. The receiver denotes the
+result and the method arguments are the operation's operands. For instance,
+given three *Decimal values a, b and c, the invocation
+
+    c.Add(a, b)
+
+computes the sum a + b and stores the result in c, overwriting whatever value
+was held in c before. Unless specified otherwise, operations permit aliasing of
+parameters, so it is perfectly ok to write
+
+    sum.Add(sum, x)
+
+to accumulate values x in a sum.
+
+(By always passing in a result value via the receiver, memory use can be much
+better controlled. Instead of having to allocate new memory for each result, an
+operation can reuse the space allocated for the result value, and overwrite that
+value with the new result in the process.)
+
+Notational convention: Incoming method parameters (including the receiver) are
+named consistently in the API to clarify their use. Incoming operands are
+usually named x, y, a, b, and so on, but never z. A parameter specifying the
+result is named z (typically the receiver).
+
+For instance, the arguments for (*Decimal).Add are named x and y, and because
+the receiver specifies the result destination, it is called z:
+
+    func (z *Decimal) Add(x, y *Decimal) *Decimal
+
+Methods of this form typically return the incoming receiver as well, to enable
+simple call chaining.
+
+Methods which don't require a result value to be passed in (for instance,
+Decimal.Sign), simply return the result. In this case, the receiver is typically
+the first operand, named x:
+
+    func (x *Decimal) Sign() int
+
+Various methods support conversions between strings and corresponding numeric
+values, and vice versa: Decimal implements the Stringer interface for a
+(default) string representation of the value, but also provides SetString
+methods to initialize a Decimal value from a string in a variety of supported
+formats (see the SetString documentation).
+
+Finally, *Decimal satisfies the fmt package's Scanner interface for scanning and
+the Formatter interface for formatted printing.
+*/
+package decimal

stdlib.go

@@ -1,4 +1,8 @@
-// This file mirrors types and constants from math/big.
+// Copyright 2020 Denis Bernard <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file mirrors constants, types and some internal functions from math/big.
 
 package decimal