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-rw-r--r--src/boot/bemol.cc108
-rw-r--r--src/include/open-axiom/InputFragment7
-rw-r--r--src/include/open-axiom/SourceInput54
-rw-r--r--src/io/InputFragment.cxx87
4 files changed, 145 insertions, 111 deletions
diff --git a/src/boot/bemol.cc b/src/boot/bemol.cc
index 64262e91..ab50f459 100644
--- a/src/boot/bemol.cc
+++ b/src/boot/bemol.cc
@@ -1,5 +1,5 @@
// -*- C++ -*-
-// Copyright (C) 2014, Gabriel Dos Reis.
+// Copyright (C) 2014-2015, Gabriel Dos Reis.
// All rights reserved.
// Written by Gabriel Dos Reis.
//
@@ -43,115 +43,11 @@
#include <stack>
#include <iterator>
#include <ctype.h>
+#include <open-axiom/SourceInput>
using namespace OpenAxiom;
//
-// -- Reading input source files --
-//
-
-// A source input transform a character stream into a program fragment
-// stream, delivering a fragment one at a time.
-struct SourceInput {
- SourceInput(std::istream& is) : input(is) { }
- // Return the next program fragment from this input source.
- Fragment get();
-
-private:
- std::istream& input;
- Line line;
-};
-
-// Return the indentation level of a line.
-// FIXME: reject or expand tabs as appropriate.
-static ColumnIndex
-indentation(const Line& line) {
- ColumnIndex idx { };
- for (auto c : line) {
- if (not isspace(c))
- break;
- ++idx;
- }
- return idx;
-}
-
-// Remove trailing white-space characters from the line.
-static Line&
-trim_right(Line& line) {
- auto n = line.length();
- while (n > 0 and isspace(line[n-1]))
- --n;
- line.resize(n);
- return line;
-}
-
-// Clean up and dress up the line with indentation information.
-static Line&
-prop_up(Line& line) {
- line.indent = indentation(trim_right(line));
- return line;
-}
-
-// Return true if line is entirely a negative comment.
-static bool
-negative_comment(const Line& line) {
- if (line.indent + 1 >= line.length())
- return false;
- return line[line.indent] == '-' and line[line.indent + 1] == '-';
-}
-
-// Return true if line is either empty or a negative comment.
-static bool
-blank(const Line& line) {
- return line.empty() or negative_comment(line);
-}
-
-// Return true if line is entirely a positive comment, i.e. a description.
-static bool
-positive_comment(const Line& line) {
- if (line.indent + 1 >= line.length())
- return false;
- return line[line.indent] == '+' and line[line.indent + 1] == '+';
-}
-
-// Decompose the input souce file into fragments, and return one
-// fragment at a time.
-Fragment
-SourceInput::get() {
- Fragment fragment;
- std::stack<ColumnIndex> indents;
-
- if (not line.empty()) {
- indents.push(line.indent);
- fragment.push_back(line);
- }
-
- while (std::getline(input, line)) {
- ++line.number;
- if (blank(prop_up(line)))
- continue; // Don't bother with ignorable comments.
- else if (fragment.line_continuation())
- ;
- else if (indents.empty()) {
- if (fragment.empty() and line.indent != 0)
- std::cout << "warning: white space at begining of fragment"
- << " on line " << line.number << '\n';
- indents.push(line.indent);
- }
- else if (line.indent == 0 and not positive_comment(fragment.back()))
- break; // A completely new line; save for later.
- else if (line.indent > indents.top())
- indents.push(line.indent);
- else {
- while (line.indent < indents.top())
- indents.pop();
- }
- fragment.push_back(line);
- }
- return fragment;
-}
-
-//
// -- Decomposing source files into lexical units of information --
//
diff --git a/src/include/open-axiom/InputFragment b/src/include/open-axiom/InputFragment
index 7f317973..65f3dfc9 100644
--- a/src/include/open-axiom/InputFragment
+++ b/src/include/open-axiom/InputFragment
@@ -1,5 +1,5 @@
// -*- C++ -*-
-// Copyright (C) 2014, Gabriel Dos Reis.
+// Copyright (C) 2014-2015, Gabriel Dos Reis.
// All rights reserved.
// Written by Gabriel Dos Reis.
//
@@ -42,9 +42,8 @@ namespace OpenAxiom {
// A physical line is just raw text, coupled with location
// information such as line and indentation column.
struct Line : std::string {
- LineNumber number;
- ColumnIndex indent;
- Line() : number(), indent() { }
+ LineNumber number { };
+ ColumnIndex indent { };
std::string sub_string(ColumnIndex s, ColumnIndex e) const {
return substr(s, e - s);
diff --git a/src/include/open-axiom/SourceInput b/src/include/open-axiom/SourceInput
new file mode 100644
index 00000000..efb4ab8b
--- /dev/null
+++ b/src/include/open-axiom/SourceInput
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+// Copyright (C) 2014-2015, Gabriel Dos Reis.
+// All rights reserved.
+// Written by Gabriel Dos Reis.
+//
+// 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 OpenAxiom, 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.
+
+#ifndef OPENAXIOM_SOURCEINPUT_included
+#define OPENAXIOM_SOURCEINPUT_included
+
+#include <iosfwd>
+#include <open-axiom/InputFragment>
+
+namespace OpenAxiom {
+ // -- A source input transform a character stream into a program fragment
+ // -- stream, delivering a fragment one at a time.
+ struct SourceInput {
+ SourceInput(std::istream& is) : input(is) { }
+ // Return the next program fragment from this input source.
+ Fragment get();
+
+ private:
+ std::istream& input;
+ Line line;
+ };
+}
+
+#endif // OPENAXIOM_SOURCEINPUT_included
diff --git a/src/io/InputFragment.cxx b/src/io/InputFragment.cxx
index dad38db2..394f670f 100644
--- a/src/io/InputFragment.cxx
+++ b/src/io/InputFragment.cxx
@@ -1,5 +1,5 @@
// -*- C++ -*-
-// Copyright (C) 2014, Gabriel Dos Reis.
+// Copyright (C) 2014-2015, Gabriel Dos Reis.
// All rights reserved.
// Written by Gabriel Dos Reis.
//
@@ -35,7 +35,10 @@
#include <open-axiom/InputFragment>
#include <algorithm>
#include <iterator>
+#include <istream>
#include <ostream>
+#include <iostream>
+#include <open-axiom/SourceInput>
namespace OpenAxiom {
// Formatting program fragments.
@@ -44,4 +47,86 @@ namespace OpenAxiom {
std::ostream_iterator<std::string>(os, "\n"));
return os;
}
+
+ // Return the indentation level of a line.
+ // FIXME: reject or expand tabs as appropriate.
+ static ColumnIndex indentation(const Line& line) {
+ ColumnIndex idx { };
+ for (auto c : line) {
+ if (not isblank(c))
+ break;
+ ++idx;
+ }
+ return idx;
+ }
+
+ // Remove trailing white-space characters from the line.
+ static Line& trim_right(Line& line) {
+ auto n = line.length();
+ while (n > 0 and isblank(line[n-1]))
+ --n;
+ line.resize(n);
+ return line;
+ }
+
+ // Clean up and dress up the line with indentation information.
+ static Line& prop_up(Line& line) {
+ line.indent = indentation(trim_right(line));
+ return line;
+ }
+
+ // Return true if line is entirely a positive comment, i.e. a description.
+ static bool positive_comment(const Line& line) {
+ if (line.indent + 1 >= line.length())
+ return false;
+ return line[line.indent] == '+' and line[line.indent + 1] == '+';
+ }
+
+ // Return true if line is entirely a negative comment.
+ static bool negative_comment(const Line& line) {
+ if (line.indent + 1 >= line.length())
+ return false;
+ return line[line.indent] == '-' and line[line.indent + 1] == '-';
+ }
+
+ // Return true if line is either empty or a negative comment.
+ static bool blank(const Line& line) {
+ return line.empty() or negative_comment(line);
+ }
+
+ // Decompose the input souce file into fragments, and return one
+ // fragment at a time.
+ Fragment SourceInput::get() {
+ Fragment fragment;
+ std::stack<ColumnIndex> indents;
+
+ if (not line.empty()) {
+ indents.push(line.indent);
+ fragment.push_back(line);
+ }
+
+ while (std::getline(input, line)) {
+ ++line.number;
+ if (blank(prop_up(line)))
+ continue; // Don't bother with ignorable comments.
+ else if (fragment.line_continuation())
+ ;
+ else if (indents.empty()) {
+ if (fragment.empty() and line.indent != 0)
+ std::cerr << "warning: white space at begining of fragment"
+ << " on line " << line.number << '\n';
+ indents.push(line.indent);
+ }
+ else if (line.indent == 0 and not positive_comment(fragment.back()))
+ break; // A completely new line; save for later.
+ else if (line.indent > indents.top())
+ indents.push(line.indent);
+ else {
+ while (line.indent < indents.top())
+ indents.pop();
+ }
+ fragment.push_back(line);
+ }
+ return fragment;
+ }
}