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22 lines
692 B
Plaintext
22 lines
692 B
Plaintext
re2c lesson 002_strip_comments, (c) M. Boerger 2006
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In this lesson you will learn how to use multiple scanner blocks and how to
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read the input from a file instead of a zero terminated string. In the end you
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will have a scanner that filters comments out of c source files but keeps re2c
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comments.
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The first scanner can be generated with:
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re2c -s -o t.c strip_001.s.re
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In the second step we will learn about YYMARKER that stores backtracking
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information.
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re2c -s -0 t.c strip_002.b.re
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The third step brings trailing contexts that are stored in YYCTXMARKER. We also
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change to use -b instead of -s option since the scanner gets more and more
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complex.
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re2c -b -0 t.c strip_002.b.re
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