さまざまな文字列操作

明解Ｃ言語入門編 > 11. 文字列とポインタ >

Ruby

# strcat 
st1 = "1234567890"
st2 = "ABCDE"

st3 = st1 + st2
printf("%s + ", st1)
printf("%s = ", st2)
printf("%s\n", st3)

st3 = st1 << st2
printf("%s + ", st1)
printf("%s = ", st2)
printf("%s\n", st3)

st3 = st1.concat(st2)
printf("%s + ", st1)
printf("%s = ", st2)
printf("%s\n", st3)
puts ""


# strrev 
printf("%s\n", st3)
ary = st3.split(//)
ary = ary.reverse
st3 = ary.join
printf("%s\n", st3)

printf("%s\n", st3.reverse)
puts ""


# strcmp 
pt1 = "123"
pt2 = "123"

i = pt1 <=> pt2
if (i == 0)
    printf("%s = %s (%d)\n", pt1, pt2, i)
elsif (i > 0)
    printf("%s > %s (%d)\n", pt1, pt2, i)
else
    printf("%s < %s (%d)\n", pt1, pt2, i)
end


pt2 = "122"
i = pt1 <=> pt2
if (i == 0)
    printf("%s = %s (%d)\n", pt1, pt2, i)
elsif (i > 0)
    printf("%s > %s (%d)\n", pt1, pt2, i)
else
    printf("%s < %s (%d)\n", pt1, pt2, i)
end

pt2 = "124"
i = pt1 <=> pt2
if (i == 0)
    printf("%s = %s (%d)\n", pt1, pt2, i)
elsif (i > 0)
    printf("%s > %s (%d)\n", pt1, pt2, i)
else
    printf("%s < %s (%d)\n", pt1, pt2, i)
end

pt2 = "999"
i = pt1 <=> pt2
if (i == 0)
    printf("%s = %s (%d)\n", pt1, pt2, i)
elsif (i > 0)
    printf("%s > %s (%d)\n", pt1, pt2, i)
else
    printf("%s < %s (%d)\n", pt1, pt2, i)
end

pt2 = "12"
i = pt1 <=> pt2
if (i == 0)
    printf("%s = %s (%d)\n", pt1, pt2, i)
elsif (i > 0)
    printf("%s > %s (%d)\n", pt1, pt2, i)
else
    printf("%s < %s (%d)\n", pt1, pt2, i)
end

pt2 = "1234"
i = pt1 <=> pt2
if (i == 0)
    printf("%s = %s (%d)\n", pt1, pt2, i)
elsif (i > 0)
    printf("%s > %s (%d)\n", pt1, pt2, i)
else
    printf("%s < %s (%d)\n", pt1, pt2, i)
end

puts ""


# strstr 
pt1 = "1234567890"
pt2 = "45"
i = pt1.index(pt2)
if i == nil
    printf("index(\"%s\", \"%s\") = nil\n", pt1, pt2)
else
    printf("index(\"%s\", \"%s\") = %d\n", pt1, pt2, i)
end

pt2 = "12"
i = pt1.index(pt2)
if i == nil
    printf("index(\"%s\", \"%s\") = nil\n", pt1, pt2)
else
    printf("index(\"%s\", \"%s\") = %d\n", pt1, pt2, i)
end

pt2 = "123456780"
i = pt1.index(pt2)
if i == nil
    printf("index(\"%s\", \"%s\") = nil\n", pt1, pt2)
else
    printf("index(\"%s\", \"%s\") = %d\n", pt1, pt2, i)
end

puts ""


# strrchr 
c = "9"
i = pt1.rindex(c)
if i == nil
    printf("rindex(\"%s\", \"%s\") = nil\n", pt1, c)
else
    printf("rindex(\"%s\", \"%s\") = %s\n", pt1, c, i)
end

c = "A"
i = pt1.rindex(c)
if i == nil
    printf("rindex(\"%s\", \"%s\") = nil\n", pt1, c)
else
    printf("rindex(\"%s\", \"%s\") = %s\n", pt1, c, i)
end

puts ""



# s
pt1 = "aabbccabcAABBCCABC"
puts pt1

pt1.sub!(/a/, "1") # "a" を "1" に
print "s/a/1/ = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.gsub!(/a/, "1") # "a" を "1" に
print "s/a/1/g = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.gsub!(/a/i, "1") # "a" を "1" に
print "s/a/1/gi = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.gsub!(/abc/i, "123") # "abc" を "123" に
print "s/abc/123/gi = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.gsub!(/abc/i, "12") # "abc" を "12" に
print "s/abc/12/gi = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.gsub!(/ac/i, "13") # "ac" を "13" に
print "s/ac/13/gi = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.tr!("a", "1") # "a" を "1" に
print "tr/a/1/ = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.tr!("^a", "1") # "a"以外 を "1" に
print "tr/a/1/c = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.tr_s!("a", "1") # "a"の連続を "1" に
print "tr/a/1/s = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.tr!("abc", "123") # "a", "b", "c" を "1", "2", "3" に
print "tr/abc/123/ = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.tr!("^abc", "1") # "a", "b", "c" 以外 を "1" に
print "tr/abc/1/ = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.tr!("abc", "12") # "a", "b", "c" を "1", "2", "2" に
print "tr/abc/12/d = ", pt1, "\n"

pt1 = "aabbccabcAABBCCABC"
pt1.tr_s!("abc", "123") # "a"の連続を "1" に。 "b"の連続を "2" に。 "c"の連続を "3" に。
print "tr/abc/123/s = ", pt1, "\n"

実行結果



L:\>ruby  l:\lesson_11_087.rb

1234567890 + ABCDE = 1234567890ABCDE

1234567890ABCDE + ABCDE = 1234567890ABCDE

1234567890ABCDEABCDE + ABCDE = 1234567890ABCDEABCDE
1234567890ABCDEABCDE

EDCBAEDCBA0987654321

1234567890ABCDEABCDE
123 = 123 (0)

123 > 122 (1)

123 < 124 (-1)

123 < 999 (-1)

123 > 12 (1)

123 < 1234 (-1)
index("1234567890", "45") = 3

index("1234567890", "12") = 0

index("1234567890", "123456780") = nil
rindex("1234567890", "9") = 8

rindex("1234567890", "A") = nil
aabbccabcAABBCCABC

s/a/1/ = 1abbccabcAABBCCABC

s/a/1/g = 11bbcc1bcAABBCCABC

s/a/1/gi = 11bbcc1bc11BBCC1BC

s/abc/123/gi = aabbcc123AABBCC123

s/abc/12/gi = aabbcc12AABBCC12

s/ac/13/gi = aabbccabcAABBCCABC

tr/a/1/ = 11bbcc1bcAABBCCABC

tr/a/1/c = aa1111a11111111111

tr/a/1/s = 1bbcc1bcAABBCCABC

tr/abc/123/ = 112233123AABBCCABC

tr/abc/1/ = aabbccabc111111111

tr/abc/12/d = 112222122AABBCCABC

tr/abc/123/s = 123123AABBCCABC