1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
-- Copyright (C) 2012, Gabriel Dos Reis.
-- 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 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.
import sys_-constants
namespace BOOT
module io where
blankChar? : %Char -> %Boolean
firstNonblankCharPosition: %String -> %Maybe %Short
trimTrailingBlank: %String -> %String
--%
--% Individual character routines
--%
++ Return true if character `c' is a space character.
macro spaceChar? c ==
c = char " "
++ Return true if character `c' is a horizontal tab character
macro tabChar? c ==
c = abstractChar 9
++ Return true if character `c' is either a space or a horitonal tab.
blankChar? c ==
spaceChar? c or tabChar? c
carriageRetChar? c ==
c = abstractChar 13
--%
--% String manipulation routines.
--%
++ Replace all characters in `s' with space characters.
storeBlank!(s,n) ==
for i in 0..maxIndex s repeat
s.i := char " "
s
++ Return the position of the first nonblank character in line, if any.
firstNonblankCharPosition line ==
or/[i for i in 0..maxIndex line | not blankChar? line.i]
trimTrailingBlank line ==
n := sz := #line
for i in (sz-1)..0 by -1 while blankChar? line.i repeat
n := n - 1
n = sz => line
subString(line,0,n)
trimCarriageReturn line ==
carriageRetChar? line.maxIndex(line) =>
subString(line,0,maxIndex line)
line
expandLeadingTabs line ==
not string? line or #line = 0 => line
line := trimCarriageReturn line
nbLoc := firstNonblankCharPosition line
indLoc := indentationLocation line
nbLoc = indLoc => line
strconc(makeString(indLoc,char " "), subString(line,nbLoc))
++ Find the position at which `s1' matches a substring of `s2',
++ starting from `k'. Return nil on failure.
findString(s1,s2,k == 0) ==
n1 := #s1
or/[i for i in k..(#s2 - n1) |
and/[stringChar(s1,j) = stringChar(s2,i+j) for j in 0..(n1-1)]]
--%
--% Source line
--% string and line number
--%
structure %SourceLine ==
Record(str: %String,no: %Short) with
sourceLineString == (.str)
sourceLineNumber == (.no)
makeSourceLine(s,n) ==
mk%SourceLine(s,n)
--%
--% Load Unit
--%
structure %LoadUnit ==
Record(path: %Path,lines: %List %SourceLine) with
loadUnitPath == (.path)
loadUnitLines == (.lines)
readLoadUnitSource path ==
lines :=
istream := inputTextFile path
or systemError ['"could not open file: ",:bright path]
try
[makeSourceLine(s,n) for n in 1.. while not eof? istream
| (s := readLine istream) and s ~= %nothing]
finally
closeStream istream
mk%LoadUnit(path,lines)
--%
--% Line abstract datatype
--%
structure %Line ==
Record(buf: %String, cchar: %Char, cidx: %Short,
lidx: %Short, no: %Short) with
lineBuffer == (.buf) -- input string buffer
lineCurrentChar == (.cchar) -- current character
lineCurrentIndex == (.cidx) -- current index
lineLastIndex == (.lidx) -- last valid index
lineNumber == (.no) -- line number
makeLine(buf == makeString 0, ch == charByName "Return",
curIdx == 1, lstIdx == 0, no == 0) ==
mk%Line(buf,ch,curIdx,lstIdx,no)
lineClear! l ==
lineBuffer(l) := makeString 0
lineCurrentChar(l) := charByName "Return"
lineCurrentIndex(l) := 1
lineLastIndex(l) := 0
lineNumber(l) := 0
++ Sets string to be the next line stored in line
lineNewLine!(s,l,no == nil) ==
sz := #s
lineLastIndex(l) := sz - 1
lineCurrentIndex(l) := 0
lineCurrentChar(l) := sz > 0 and s.0 or charByName '"Return"
lineBuffer(l) := s
lineNumber(l) := no or (lineNumber l + 1)
++ Tests if line is empty or positioned past the last character
lineAtEnd? l ==
lineCurrentIndex l >= lineLastIndex l
++ Tests if line is empty or positioned past the last character
linePastEnd? l ==
lineCurrentIndex l > lineLastIndex l
++ Buffer from current index to last index
lineCurrentSegment l ==
lineAtEnd? l => makeString 0
subSequence(lineBuffer l,lineCurrentIndex l,lineLastIndex l)
lineNextChar l ==
lineBuffer(l).(1 + lineCurrentIndex l)
lineAdvanceChar! l ==
n := lineCurrentIndex l + 1
lineCurrentIndex(l) := n
lineCurrentChar(l) := lineBuffer(l).n
--%
--% Reader
--%
structure %Reader ==
Record(lu: %LoadUnit,est: %OutputStream,
lines: %List %String,sline: %Line,idx: %Short,nxt: %SourceLine) with
readerUnitSource == (.lu) -- current load unit source
readerError == (.est) -- error output stream
readerPendingLines == (.lines)
readerSourceLine == (.sline) -- current input line
readerLineNumber == (.idx) -- current line number
readerNextLines == (.nxt) -- next source line to process
makeReader(path,est) ==
lu := readLoadUnitSource path
mk%Reader(lu,est,nil,makeLine(),0,loadUnitLines lu)
readerEoi? rd ==
readerNextLines rd = nil
readerReadLine rd ==
readerNextLines rd is [x,:xs] =>
readerNextLines(rd) := xs
sourceLineString x
%nothing
++ Add line `l' to the stack of pending lines.
readerDeferLine(rd,l) ==
readerPendingLines(rd) := [l,:readerPendingLines rd]
++ Print current line into to the reader's error stream.
readerPrintCurrentLine rd ==
l := readerSourceLine rd
if linePastEnd? l then
formatToStream(readerError rd,'"~&The current line is empty.~%")
else
formatToStream(readerError rd,'"~&The current line is:~%~%")
formatToStream(readerError rd,'"~&~5D> ~A~%",lineNumber l,lineBuffer l)
formatToStream(readerError rd,'"~v@T^~%",lineCurrentIndex l + 7)
|
