10. The Language Specification - Comparisons¶
This section contains a list of comparison operators. They all take two arguments and return a boolean value depending on the relationship between the two arguments.
10.1. “<” - Is Less Than¶
Arity: 2
10.1.1. Any a, Same Type b: Less Than¶
If a and b are of the same type, checks if a is less than b by whatever way that type is compared (e.g. Numbers by size, strings lexicographically).
Ex:
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<5T<T5
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Pprint("\n",lt(5,T))
Pprint("\n",lt(T,5))
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True
False
10.1.2. Seq a, Int b: Slice Till¶
Takes a slice of sequence a until index b. This is equivalent to the Python statement a[:b]. The slice is not inclusive of the element at index b
Ex:
<"abcdefgh"5
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Pprint("\n",lt("abcdefgh",5))
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abcde
10.1.3. Set a, Set b: Is Subset¶
Checks if set a is a subset of set b. This means that it checks if set b contains all the elements of set a.
Ex:
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<{[1 2){[1 2 3)
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Pprint("\n",lt(Pset(Plist(1,(2))),Pset(Plist(1,(2),(3)))))
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True
10.2. “q” - Is Equal To¶
Arity: 2
This checks if the two values are equal to each other. This is the same as the Python ==.
Ex:
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qT5qTT
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Pprint("\n",equal(T,5))
Pprint("\n",equal(T,T))
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False
True
10.3. “>” - Is Greater Than¶
Arity: 2
10.3.1 Any a, Same Type b: Greater Than¶
This checks if a is greater than b. Uses the same type of comparisons as <
Ex:
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>5T>T5
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Pprint("\n",gt(5,T))
Pprint("\n",gt(T,5))
==================================================
False
True
10.3.2 Seq a, Int b: Slice From¶
This takes a slice of sequence a from index b onwards till the end. This is equivalent to the Python a[b:]. The slice is inclusive of the element at index b.
Ex:
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>"abcdefgh"5
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Pprint("\n",gt("abcdefgh",5))
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fgh
10.3.3. Set a, Set b: Is Superset¶
Checks is set a is a superset of set b. This means that it checks if set a contains all the elements of set b. This does not return True if the two sets are equal.
Ex:
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>{[1 2 3){[1 2)
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Pprint("\n",gt(Pset(Plist(1,(2),(3))),Pset(Plist(1,(2)))))
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True
10.4. “n” - Not Equal To¶
Arity: 2
Checks if the two elements are not equal to each other. This is equivalent to Python’s ”!=”.
Ex:
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nT5nTT
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Pprint("\n",ne(T,5))
Pprint("\n",ne(T,T))
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True
False
10.5. “g” - Is Greater Than or Equal To¶
Arity: 2
10.5.1. Any a, Same Type b: Greater Than or Equal To¶
Checks if a is greater than or equal to b.
Ex:
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gT5gTTg5T
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Pprint("\n",gte(T,5))
Pprint("\n",gte(T,T))
Pprint("\n",gte(5,T))
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True
True
False
10.5.2. Seq a, Int b: Slice From, 1-indexed¶
This takes a slice of a, from the element b-1. It is equivalent to a[b-1:].
Ex:
==================== 3 chars =====================
gG5
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Pprint("\n",gte(G,5))
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efghijklmnopqrstuvwxyz
10.5.3. Set a, Set b: Superset or Equal¶
Checks if set a is a superset of set b or equal to set b.
Ex:
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g{[1 2 3){[2 3)g{[1 2 3){[1 2 3)
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Pprint("\n",gte(Pset(Plist(1,(2),(3))),Pset(Plist(2,(3)))))
Pprint("\n",gte(Pset(Plist(1,(2),(3))),Pset(Plist(1,(2),(3)))))
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True
True
10.6. “}” - Contains¶
Arity: 2
Checks if the second argument, a collection, contains the first argument. Is equivalent to the Python in operator.
Ex:
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}\a"abc"
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Pprint("\n",("a" in "abc"))
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True