Update pl0 for ebnf changes, and add more tests

db4
Chris Double 2008-03-19 18:35:45 +13:00
parent eef6ae7827
commit 208c88c449
2 changed files with 105 additions and 18 deletions

View File

@ -1,7 +1,7 @@
! Copyright (C) 2007 Chris Double.
! See http://factorcode.org/license.txt for BSD license.
!
USING: kernel tools.test peg peg.pl0 ;
USING: kernel tools.test peg peg.pl0 multiline sequences ;
IN: peg.pl0.tests
{ "abc" } [
@ -11,3 +11,89 @@ IN: peg.pl0.tests
{ 55 } [
"55abc" number parse parse-result-ast
] unit-test
{ t } [
<"
VAR x, squ;
PROCEDURE square;
BEGIN
squ := x * x
END;
BEGIN
x := 1;
WHILE x <= 10 DO
BEGIN
CALL square;
x := x + 1;
END
END.
"> program parse parse-result-remaining empty?
] unit-test
{ f } [
<"
CONST
m = 7,
n = 85;
VAR
x, y, z, q, r;
PROCEDURE multiply;
VAR a, b;
BEGIN
a := x;
b := y;
z := 0;
WHILE b > 0 DO BEGIN
IF ODD b THEN z := z + a;
a := 2 * a;
b := b / 2;
END
END;
PROCEDURE divide;
VAR w;
BEGIN
r := x;
q := 0;
w := y;
WHILE w <= r DO w := 2 * w;
WHILE w > y DO BEGIN
q := 2 * q;
w := w / 2;
IF w <= r THEN BEGIN
r := r - w;
q := q + 1
END
END
END;
PROCEDURE gcd;
VAR f, g;
BEGIN
f := x;
g := y;
WHILE f # g DO BEGIN
IF f < g THEN g := g - f;
IF g < f THEN f := f - g;
END;
z := f
END;
BEGIN
x := m;
y := n;
CALL multiply;
x := 25;
y := 3;
CALL divide;
x := 84;
y := 36;
CALL gcd;
END.
"> program parse parse-result-remaining empty?
] unit-test

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@ -1,30 +1,31 @@
! Copyright (C) 2007 Chris Double.
! See http://factorcode.org/license.txt for BSD license.
USING: kernel arrays strings math.parser sequences
peg peg.ebnf peg.parsers memoize ;
peg peg.ebnf peg.parsers memoize namespaces ;
IN: peg.pl0
#! Grammar for PL/0 based on http://en.wikipedia.org/wiki/PL/0
MEMO: ident ( -- parser )
CHAR: a CHAR: z range
CHAR: A CHAR: Z range 2array choice repeat1
[ >string ] action ;
[
CHAR: a CHAR: z range ,
CHAR: A CHAR: Z range ,
] choice* repeat1 [ >string ] action ;
MEMO: number ( -- parser )
CHAR: 0 CHAR: 9 range repeat1 [ string>number ] action ;
<EBNF
program = block '.' .
block = [ 'const' ident '=' number { ',' ident '=' number } ';' ]
[ 'var' ident { ',' ident } ';' ]
{ 'procedure' ident ';' [ block ';' ] } statement .
statement = [ ident ':=' expression | 'call' ident |
'begin' statement {';' statement } 'end' |
'if' condition 'then' statement |
'while' condition 'do' statement ] .
condition = 'odd' expression |
expression ('=' | '#' | '<=' | '<' | '>=' | '>') expression .
expression = ['+' | '-'] term {('+' | '-') term } .
term = factor {('*' | '/') factor } .
factor = ident | number | '(' expression ')'
program = block "."
block = [ "CONST" ident "=" number { "," ident "=" number } ";" ]
[ "VAR" ident { "," ident } ";" ]
{ "PROCEDURE" ident ";" [ block ";" ] } statement
statement = [ ident ":=" expression | "CALL" ident |
"BEGIN" statement {";" statement } "END" |
"IF" condition "THEN" statement |
"WHILE" condition "DO" statement ]
condition = "ODD" expression |
expression ("=" | "#" | "<=" | "<" | ">=" | ">") expression
expression = ["+" | "-"] term {("+" | "-") term }
term = factor {("*" | "/") factor }
factor = ident | number | "(" expression ")"
EBNF>