[Question]
  [
A lipogram is a block of words that omits a particular symbol. Right now, I am avoiding our fifth symbol of 26 that commonly show up. You should know by now what I am omitting. If not, look up "lipogram" and you will know.
## Your Task
With a char, a blank, and a following string (blanks may show up in this; with only ASCII 32-126 chars) in input, output falsy if this char is in input string, truthy if not. This char that you must look for will always fit in two spans: "A" to "Z" or "a" to "z" (ASCII 65-90, 97-122). Do not distinguish capitals and non-capitals. Also, don't worry about blanks or punctuation symbols. Both programs and functions satisfy. Also, you may split input char and string into two args for programs or functions, and string as first arg is okay.
## Illustrations
### Truthy
```
e This is a lipogram.
a You need to consider other letters too.
E Capitals also count.
```
### Falsy
```
e This sentence is not a lipogram (for e).
t This particular letter is surprisingly hard.
A You don't need to care about any non-alphabetic symbols.
```
---
### Non-lipogrammed version
A lipogram is a series of words that leaves out a letter. I left out the letter "e" above.
Your task is to take a character and a string (which may include spaces) as input, separated by a space or newline, and output falsy if the character is in the string, and truthy otherwise. You may assume the string is composed solely of printable ASCII characters (char codes 32-126). The character will always be in the English alphabet, and there is no difference between lowercase and uppercase. The character will not be a space or symbol. You may write a program or a function. For either, you may take the character and string as separate arguments, and the string may come first.
  
[Answer]
# C, 42 bytes
```
#define f(c,s)!strchr(s,c)&!strchr(s,c^32)
```
[Answer]
## Javascript ES6 ~~34~~ ~~26~~ 23 Bytes
```
x=>!/^(.).*\1/i.test(x)
```
shaved 8 bytes thanks @MartinBüttner
[Answer]
# [05AB1E](https://github.com/Adriandmen/05AB1E), ~~7~~ ~~6~~ ~~4~~ 3 bytes
Code:
```
l`-
```
Explanation:
```
l     # Convert both elements to lowercase
 `    # Flatten the array
  -   # Loop over the second line of text and substract each char from the first character
        For example: "abcde""ba"- would result in "cde"
```
[Try it online!](http://05ab1e.tryitonline.net/#code=bGAt&input=WyJFIiwgIlRoaXMgaXMgYSBsaXBvZ3JhbS4iXQ)
Truthy is when the current letter is outputted. Falsy is when nothing is outputted.
[Answer]
# TeaScript, ~~5~~ 3 bytes
```
AµN
```
Aha \o/! I forgot about implicit input! TeaScript will automatically insert `x.` (the input) at the beginning. I can then check if it has the other input (in variable `µ`) and so a NOT (`N`). I guess TeaScript's best advantage here is its implicit input 
[Try it online](http://vihan.org/p/TeaScript/#?code=%22A%C2%B5N%22&inputs=%5B%22This%20sentence%20is%20not%20a%20lipogram%22,%22e%22%5D&opts=%7B%22ev%22:false,%22debug%22:false,%22nox%22:false%7D)
## Explanation
```
  A µ  N
x.A(y).N  // At compile time
x.A // input, has...
(y) // second input
N   // Logical NOT
```
[Answer]
## Bash, ~~16~~ 11 bytes
```
grep -iv $1
```
`-i` is the case-insensitive flag, `-v` inverts (checks for a non-match).
Character must be provided as a command line argument, and the test string on STDIN.
Reduced by 5 bytes with @[DigitalTrauma](https://codegolf.stackexchange.com/users/11259/digital-trauma)'s help!
Sample runs:
```
llama@llama:~$ echo 'This is a lipogram' | ./lipogram.sh e
This is a lipogram.
llama@llama:~$ echo 'This sentence is not a lipogram (for e).' | ./lipogram.sh e
```
[Answer]
# Japt, ~~12~~ ~~6~~ 4 bytes
```
!VoU
```
[Test it online!](http://ethproductions.github.io/japt?v=master&code=IVZvVQ==&input=ImUiICJUaGlzIGlzIGEgbGlwb2dyYW0uIg==)
@Downgoat's TeaScript answer reminded me that Japt has exactly the same built-in, cutting off a final two bytes.
### How it works
```
       // Implicit: U = input char, V = input string
VoU    // Keep only the chars in V that are equal to U, ignoring case.
!      // Take logical NOT. Returns true if no matches were found, false otherwise.
```
[Answer]
## JavaScript (ES6), 29 bytes
```
(c,s)=>!RegExp(c,'i').test(s)
```
[Answer]
## CJam, 6 byte
```
lel(&!
```
[Try it online!](http://cjam.tryitonline.net/#code=bGVsKCYh&input=QSBZb3UgZG9uJ3QgbmVlZCB0byBjYXJlIGFib3V0IGFueSBub24tYWxwaGFiZXRpYyBzeW1ib2xzLg) lel
### Explanation
```
l  e# Read a line of input.
el e# Convert to lower case.
(  e# Pull off the first character.
&  e# Set intersection with the rest of the input.
!  e# Logical NOT.
```
[Answer]
# Python 3, 36
Having to ignore case is surprisingly expensive.
```
lambda a,b:a.lower()not in b.lower()
```
Takes the arguments as (char, string)
[Answer]
## Perl, 11 + 1 = 12 bytes
```
$_=lc!~lc<>
```
Requires the `-p` switch and takes input as `$string\n$letter`
```
$ perl -pe'$_=lc!~lc<>' <<< $'this is a lipogram\ne'
1
```
How it works:
```
            # -p auto reads input into $_ and auto prints at the end
   lc       # lowercase $_
     !~     # Check against regex
       lc<> # Read next line and lowercase it. '=~' will expect the rValue to be
            # a regex and therefore the result from 'lc<>' will be treated as such
$_=         # Assign result ('1' or '') to $_ which will be printed
```
[Answer]
## Pyth, ~~8~~ 7 bytes
```
-rz0rw0
```
Explanation
```
 rw0    -  input().lower()
-       - ^ - V
    rw0 -  input().lower()
```
Thanks [@FryAmTheEggman](https://codegolf.stackexchange.com/users/31625/fryamtheeggman) for telling me I can use `-` instead of `!}`
[Try it here](http://pyth.herokuapp.com/?code=!%7Drw0rw0&input=e%0AThis+is+a+lipogram.&debug=0)
[Answer]
# Julia 0.3, ~~22~~ 20 bytes
```
c%s=c&95∉[s...]&95
```
`uppercase` is a *long* word.
### How it works
```
c%s=c&95∉[s...]&95
c%s=                Redefine the binary operator % so it takes a character c and
                    a string s and...
     c&95                Compute lo bitwise AND of c and 95.
                         This casts the character c to uppercase.
          [s...]         Yield the list of the characters of the string s.
                &95      Compute lo bitwise AND of each chararacter and 95.
                         This casts the characters of s to uppercase.
         ∉               Return a Boolean, signaling non-membership.
```
[Answer]
## Java, 63 bytes.
```
boolean f(String s,char c){return!s.matches("(?i:.*"+c+".*)");}
```
[Answer]
# O, 8 bytes
```
{_.@_-=}
```
An anonymous function that takes a character and a string.
[Try it online.](http://o-lang.herokuapp.com/link/J1QidGVzdCJ7Xy5AXy09fX4=/)
## Explanation
```
{_.@_-=}
{      }
 _        Lowercase string
  .       Duplicate
   @      Rotate stack
    _     Lowercase character
     -    Remove all instances of the character
      =   Compare to original
```
[Answer]
## PowerShell, ~~36~~ ~~32~~ ~~30~~ ~~29~~ 25 bytes
```
param($a,$b)$b-notmatch$a
```
Uses the [`-notmatch` operator](https://technet.microsoft.com/en-us/library/hh847759(v=wps.620).aspx), and simply outputs `True` or `False`.
[Answer]
# [MATL](https://esolangs.org/wiki/MATL), 5 bytes
```
kikm~
```
[**Try it online!**](http://matl.tryitonline.net/#code=a2lrbX4&input=J3QnCidUaGlzIHBhcnRpY3VsYXIgbGV0dGVyIGlzIHN1cnByaXNpbmdseSBoYXJkLic)
```
k        % take first input (letter) implicitly. Convert to lowercase
ik       % take second input (text). Convert to lowercase
m        % ismember function
~        % negate
```
[Answer]
## Seriously, 6 bytes
```
,ù,ùíu
```
[Try it online!](http://seriously.tryitonline.net/#code=LMO5LMO5w611&input=J1RoaXMgc2VudGVuY2UgaXMgbm90IGEgbGlwb2dyYW0gKGZvciBlKS4nCidFJw)
Takes input as `'string'\n'char'`
Explanation:
```
,ù,ùíu
,ù      get string (lowercase)
  ,ù    get char (lowercase)
    íu  1-based index (0 if not found)
```
[Answer]
# Retina, 11
```
iA`^(.).*\1
```
I'm not sure what counts as truthy / falsy in Retina, this will echo the line if it is a lipogram for the given character, and it will return the empty string if it isn't.
This will also work for multiline input.
[Try it online!](http://retina.tryitonline.net/#code=aUFgXiguKS4qXDE&input=ZSBUaGlzIGlzIGEgbGlwb2dyYW0uCmEgWW91IG5lZWQgdG8gY29uc2lkZXIgb3RoZXIgbGV0dGVycyB0b28uCkUgQ2FwaXRhbHMgYWxzbyBjb3VudC4KCmUgVGhpcyBzZW50ZW5jZSBpcyBub3QgYSBsaXBvZ3JhbSAoZm9yIGUpLgp0IFRoaXMgcGFydGljdWxhciBsZXR0ZXIgaXMgc3VycHJpc2luZ2x5IGhhcmQuCkEgWW91IGRvbid0IG5lZWQgdG8gY2FyZSBhYm91dCBhbnkgbm9uLWFscGhhYmV0aWMgc3ltYm9scy4)
[Answer]
## [Minkolang 0.15](https://github.com/elendiastarman/Minkolang), 10 bytes
```
$or7Z0Z,N.
```
[Try it here.](http://play.starmaninnovations.com/minkolang/?code=%24or7Z0Z%2CN%2E&input=e%20This%20is%20a%20lipogram%2E)
### Explanation
```
$o            Read in whole input as characters
  r           Reverse stack
   7Z         Lowercase everything
     0Z       Pop top of stack (a) and count how many 'a's are in the stack
       ,      'not' the top of stack
        N.    Output as number and stop.
```
[Answer]
## Rust, 75 bytes
```
|c:char,s:&str|!s.to_lowercase().contains(c.to_lowercase().next().unwrap())
```
Biggest score means I win, right? >\_<
[Try it here.](http://is.gd/gzgTSB)
[Answer]
# Jelly, 8 bytes
```
ḢO^O&95P
```
[Try it online!](http://jelly.tryitonline.net/#code=4biiT15PJjk1UA&input=&args=QyBKZWxseSBzaG91bGQgcmVhbGx5IGhhdmUgc3RyaW5nIG1hbmlwdWxhdGlvbiBieSBub3cu)
### How it works
```
ḢO^O&95P  Main link. Input: S (string)
Ḣ         Pop the first character of S.
 O        Ordinal; compute its code point.
  ^O      XOR it with the code points of the remaining characters.
    &95   AND each result with 95.
       P  Take the product of the results.
```
[Answer]
## Python, 34 bytes
```
lambda c,s:c not in s+s.swapcase()
```
Checks for character `c` being in string `s`, ignoring case by appending a case-swapped copy of `s` to `s`. The negation is done with `not`, which looks lengthy but I don't see better. This is same length:
```
lambda c,s:(c in s+s.swapcase())<1
```
You can't omit the parens or else Python will interpet the expression as a chained three-value inequality of form `_ in _ < _`.
Python 3.5 should allow 33 bytes via set conversions, though I can't test it now.
```
lambda c,s:{*c}-{*s+s.swapcase()}
```
[Answer]
## Pyke, 7 bytes
```
Dl3+R{!
```
Explanation:
```
D       -     eval_or_not(input()).lower()
 l3     -    ^.swapcase()
   +    -   ^+^
    R   -  rotate 2
     {  -  ^ in ^
      ! - not ^
```
[Answer]
# JavaScript ES6, ~~41~~ 40 bytes
```
x=>!~x.slice(2).search(RegExp(x[0],"i"))
```
Takes the entire string as an argument. I cannot save bytes by accepting two different arguments because then my answer would melt into the other ES6 answer :(
[Answer]
# CJam, 10 bytes
```
{el\ele=!}
```
An anonymous function (block) that takes a character (not a string!) and a string.
[Try it online.](http://cjam.tryitonline.net/#code=J0EiYWJjIntlbFxlbGU9IX1-&input=)
## Explanation
```
{el\ele=!}
{        }
 el\el      lowercase both args
      e=    count occurrences of the character
        !   logical not
```
[Answer]
# R, 26 bytes
```
 function(x,y)!grepl(y,x,T)
```
x is the string, y is the letter, the T in the call to grepl makes it case insensitive.
[Answer]
# Jolf, ~~6~~ 7 bytes
So. Many. Sixes. SMS? Well, [try it here](http://conorobrien-foxx.github.io/Jolf/#code=fyBNaUknaQ) nonetheless. Replace `⌂` with `\x7f`.
```
⌂ MiI'i
⌂_M      match with flags
   i     the input
    I    with another input
     'i  using i as a flag
```
[Answer]
# [Vyxal](https://github.com/Vyxal/Vyxal), 6 bytes
```
ɽfhO2<
```
[Try it Online!](https://vyxal.pythonanywhere.com/#WyJQQSIsIiIsIsm9ZmhPMjwiLCIiLCIiXQ==)
Accepts one line as input, formatted like the test cases.
How it works:
```
ɽf          # convert input to lowercase and turn into list
  hO        # count the number of times the first item in the list occurs
     2<     # is it less than 2 (should only occur once as the first character)
```
[Answer]
## Ruby, 17 bytes
```
->c,s{/#{c}/i!~s}
```
```
->c,s{  # lambda with two arguments
/#{c}/  # turn the input character into a regexp w/ interpolation
i       # case insensitive
!~      # does not match
s       # input string
}
```
[Answer]
## Batch, 53 bytes
```
@set s=%2
@call set t=%%s:%1=%%
@if %s%==%t% echo 1
```
Accepts input as two command-line arguments. (Quote the second argument if necessary.) Outputs 1 on success, nothing if the first argument is (insensitively) found in the second.
]