Merge: nitunit the manual

[nit.git] / doc / manual / structure.md

diff --git a/doc/manual/structure.md b/doc/manual/structure.md
index ba1107f..b3a319d 100644 (file)
--- a/doc/manual/structure.md
+++ b/doc/manual/structure.md
@@ -23,14 +23,16 @@ Note that the control flow is determined only from the position, the
 order and the nesting of the control structures. The real value of the
 expressions used has no effect on the control flow analyses.
 
-~~~
+~~~nitish
 if true then
     return
 else
     return
 end
 print 1 # Compile error: unreachable statement
+~~~
 
+~~~
 if true then
     return
 end
@@ -40,18 +42,24 @@ print 1 # OK, but never executed
 ## if
 
 ~~~
-if exp then stm
-if exp then stm else stm
+var exp = true
+# ...
+if exp then print 1
+if exp then print 2 else print 2
 if exp then
-    stms
+    print 1
+    print 2
 end
 
 if exp then
-    stms
+    print 1
+    print 2
 else if exp then
-    stms
+    print 10
+    print 20
 else
-    stms
+    print 100
+    print 200
 end
 ~~~
 
@@ -60,17 +68,21 @@ syntactically complete thus the newline terminate the whole `if`
 structure; then an error is signaled since a statement cannot begin with
 `else`.
 
-~~~
-if exp then stm # OK: complete 'if' structure
-else stm # Syntax error: unexpected 'else'
+~~~nitish
+if exp then print 1 # OK: complete 'if' structure
+else print 2 # Syntax error: unexpected 'else'
 ~~~
 
 ## while
 
 ~~~
-while exp do stm
-while exp do
-    stms
+var x = 0
+while x < 10 do x += 1
+print x # outputs 10
+
+while x < 20 do
+    print x # outputs 10 11 ... 19
+    x += 1
 end
 ~~~
 
@@ -79,9 +91,9 @@ end
 `for` declares an automatic variable used to iterates on `Collection` (`Array` and `Range` are both `Collection`).
 
 ~~~
-for x in [1..5] do print x # outputs 1 2 3 4 5
-for x in [1, 4, 6] do
-    print x # outputs 1 4 6
+for i in [1..5] do print i # outputs 1 2 3 4 5
+for i in [1, 4, 6] do
+    print i # outputs 1 4 6
 end
 ~~~
 
@@ -90,8 +102,8 @@ end
 Step can also be used to specify the size of each increment at the end of a for cycle.
 
 ~~~
-for x in [9 .. 4].step(-1) do print x # outputs 9 8 7 6 5 4
-for x in [9 .. 4[.step(-2) do print x # outputs 9 7 5
+for i in [9 .. 4].step(-1) do print i # outputs 9 8 7 6 5 4
+for i in [9 .. 4[.step(-2) do print i # outputs 9 7 5
 ~~~
 
 ## loop
@@ -100,9 +112,9 @@ Infinite loops are mainly used with breaks. They are useful to implement *until*
 
 ~~~
 loop
-    stms
+    print 1
     if exp then break
-    stms
+    print 2
 end
 ~~~
 
@@ -114,10 +126,10 @@ Single `do` are used to create scope for variables or to be attached with labele
 
 ~~~
 do
-    var x = 5
-    print x
+    var j = 5
+    print j
 end
-# x is not defined here
+# j is not defined here
 ~~~
 
 ## break, continue and label
@@ -127,9 +139,10 @@ Unlabeled `break` exits the current `for`, `while`, `loop`, Unlabeled `continue`
 `label` can be used with `break` or `continue` to act on a specific control structure (not necessary the current one). The corresponding `label` must be defined after the `end` keyword of the designated control structure.
 
 ~~~
-for i in [0..width[ do
-    for j in [0..height[ do
-        if foo(i, j) then break label outer_loop
+for i in [0..10[ do
+    for j in [0..10[ do
+        if i + j > 15 then break label outer_loop
+       print "{i},{j}"
         # The 'break' breaks the 'for i' loop
     end
 end label outer_loop
@@ -139,9 +152,9 @@ end label outer_loop
 
 ~~~
 do
-    stmts
-    if expr then break label block
-    stmts
+    print 1 # printed
+    if exp then break label block
+    print 2 # not printed because exp is true
 end label block
 ~~~
 
@@ -154,9 +167,9 @@ end label block
 `assert` verifies that a given Boolean expression is true, or else it aborts. An optional label can be precised, it will be displayed on the error message. An optional `else` can also be added and will be executed before the abort.
 
 ~~~
-assert bla: whatever else
-    # "bla" is the label
-    # "whatever" is the expression to verify
+assert bla: exp else
+    # `bla` is the label
+    # `exp` is the expression to verify
     print "Fatal error in module blablabla."
     print "Please contact the customer service."
 end