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Can service stuff (like giveme's) be merged into normal classes?
================================================================
Super-simple solution with default values
-----------------------------------------
Perhaps add a keyword for implicit parameters:
param int x = 0
int y
constructor
int half_y
code
this.y = 2 * half_y
end
This allows (type, name, default-value) to be specified. That would be
enough for many cases, but it feels a bit too limiting.
More powerful syntaxes
----------------------
# Current syntax:
# The good part is that it's not possible to "sneak in" some
# capability somewhere else (but that can be prevented with normal
# fields also).
giveme
int x = param "-x,--x-value" 0
end
# This has two types, which can be redundant.
int x from CliParam "-x,--x-value" 0
# This syntax is compact, but how intuitive is the distinction
# between `:` and `=` ?
# Also, `:` is used in many languages for indicating a type.
int x : param "-x,--x-value" 0
# Better than the above? Somewhat intuitive also.
int x from param "-x,--x-value" 0
HttpRequest req from default
Replace constructors with giveme's?
-----------------------------------
For example:
# Definition of `SomeType`
giveme
File f
end
data
long filepos
end
entry initialize
code
filepos = 0
end
# Usage
entry main
code
File f = new
f.open "test.txt"
SomeType st = new
st.f = f
st.init
end
# Usage, with implicit(!) creation on first use:
entry main
code
File f
f.open "test.txt"
SomeType st
st.f = f
st.init
end
Or even replace both with typestates:
# Definition of `SomeType`
data
File f
when initialized
long filepos
end
entry initialize
transition
initialized
code
filepos = 0
end
# Usage
entry main
code
SomeType st
end
Or, even more general:
data
after created
File f
after initialized
long filepos
end
func initialize
transition
created to initialized
code
filepos = 0
end
|
